Methods for expressing proteins in axons

ABSTRACT

The invention relates to expressing proteins in the axons of mammalian polypeptide in neuronal axons, viruses that can be used deliver nucleic acids of the invention into neuronal axons, as well as methods for doing so. Thus, the invention provides pharmaceutical compositions comprising viruses of the invention, as well as their use in methods of treating injured axons or conditions associated with aberrant axon growth or function.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a national stage application under 35 U.S.C. §371 of PCT/US2009/00118, filed Jan. 9, 2009 and published as WO 2009/089040 on Jul. 16, 2009, which claims priority to U.S. Provisional Application Ser. No. 61/010,720, filed Jan. 11, 2008, the contents of which applications are specifically incorporated herein by reference in their entirety.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

Work relating to this application was supported by a grant from the National Institutes of Mental Health (5R01MH066204-05). The government may have certain rights in the invention.

BACKGROUND OF THE INVENTION

Neurons have axons, which are long extensions that typically connect the neuron to a target cell, such as another neuron, or a muscle cell. Axons can be very long. For example, while the cell body may be 40 microns in diameter, the axon of many sensory neurons can be a meter or longer in adults.

There are several types of medical conditions that are associated with axonal injury. These include numerous types of axonopathies, ranging from Charcot-Marie-Tooth disease to diabetic neuropathy, as well as traumatic injuries of axons, such as spinal cord injury (SCI). SCI is caused by injury to axonal tracts that descend from the brain. These axons are derived from upper motor neurons that are situated in the cortex that send axons through the brain, down through the spinal cord, where they eventually synapse on lower motor neurons in the spinal cord. Injury to these descending axons, results in the loss of innervation of motor neurons, and therefore paralysis of the muscles that are innervated by those motor neurons.

Thus, there is a need for methods of promoting axonal regeneration or growth after injury.

SUMMARY OF THE INVENTION

The invention is based on the discovery that proteins can be expressed in the axons of a mammalian neuron. More specifically, the invention involves the discovery that a protein coding sequence operably linked to an internal ribosome entry site (IRES) in an RNA viral genome can be expressed in a mammalian axon when the RNA genome is transduced into the axon. Thus, the invention provides isolated recombinant nucleic acids such as DNA and RNA molecules, as well as RNA viruses that can be used to deliver selected polypeptide-coding sequences into the axons of mammalian neurons for expression of the encoded polypeptides in the axons. The invention also provides methods for expressing polypeptides in the axons of mammalian neurons as well as methods of treating injured axons or treating conditions associated with aberrant axon function.

In one aspect, the invention provides an isolated nucleic acid that has (a) a mammalian translation initiation element; (b) a polypeptide coding sequence operably-linked to the mammalian translation initiation element, and (c) a viral packaging sequence. The coding sequence encodes a polypeptide that, when expressed in the axon of a mammalian neuron, modulates the growth or function of an axon. In some embodiments, the viral packaging sequence is that of an alphavirus. In some embodiments, the alphavirus is a Sindbis virus or a Semliki forest virus. In some embodiments, the nucleic acid further includes one or more viral structural protein coding sequences such as an alphavirus protein coding sequence, which can be a capsid protein or a glycoprotein involved in viral assembly and packaging.

In some embodiments, the nucleic acid is a recombinant RNA molecule. In some embodiments, the RNA molecule includes a poly-adenylyl tail. In some embodiments, mammalian translation initiation element of the recombinant RNA molecule is a 5′CAP. In other embodiments, it is an internal ribosome entry site (IRES).

In some embodiments, the nucleic acid is a recombinant DNA molecule that further comprises a mammalian promoter sequence located 5′ of the mammalian translation initiation element and wherein the mammalian translation initiation element is an IRES.

In some embodiments, the IRES of the a nucleic acid of the invention can be a viral IRES, such as the IRES from encephalomyocarditis, Sindbis virus or a Semliki forest virus. In other embodiments, the IRES can be a prokaryotic or eukaryotic sequence. In some embodiments, the IRES has the sequence of any one of SEQ ID NO: 29-35. In some embodiments, the RNA molecule is a single-stranded genome of a virus or an attenuated mutant thereof that is capable of infecting the axon of a mammalian neuron and tranducing the recombinant RNA molecule into the axon.

In some embodiments, the polypeptide encoded by a nucleic acid of the invention promotes the growth of an injured axon. In one embodiment, the polypeptide-coding sequence encodes a kinase or a transcription factor. The kinase can be a src kinase, the transcription factor can be a cyclic AMP-response element-binding protein (CREB) or nervy. In some embodiments, the polypeptide-coding sequence encodes a C3-ADP-ribosyltransferase, a dominant-negative RhoA mutant polypeptide, a cAMP-producing enzyme, glutamic acid decarboxylase, human proenkephalin, an inhibitor of a dominant-negative Vps24, an intestinal peptide (VIP), brain-derived neurotrophic factor (BDNF), neurotrophin-3 (NT-3), glial-derived neurotropic factor (GDNF), GAP 43 or CAP23. The dominant-negative RhoA mutant polypeptide can be N19-RhoA polypeptide. The cAMP-producing enzyme can be a soluble adenylyl cyclase. In some embodiments, the polypeptide comprises the sequence of any one of SEQ ID NO: 36 to 47. In some embodiments, the polyeptide-coding sequence comprises the sequence of any one of SEQ ID NO: 49 to 60.

In one aspect, the invention provides a recombinant RNA virus capable of infecting the axon of a mammalian neuron, the virus comprising the RNA molecule of the invention. In some embodiments, the RNA molecule encodes a polypeptide having the sequence of any one of SEQ ID NO: 36 to 47. In some embodiments, the RNA molecule comprises the sequence of any one of SEQ ID NO: 49 to 60. The virus can be an alphavirus or an attenuated form thereof such as a Semliki forest virus or an attenuated form thereof

In one aspect, the invention provides a composition comprising a recombinant RNA virus of the invention and a pharmaceutically acceptable carrier.

In one aspect, the invention provides a method for expressing a polypeptide in the axon of a mammalian neuron comprising contacting the axon with a virus or composition of the invention, under conditions effective for the transduction of the recombinant RNA molecule in the virus into the axon. The polypeptide can be any one described here including one capable of modulating the growth or function of an axon, e.g. one capable of promoting the growth of an injured axon or reducing the activity of the axon of a neuron. Examples include a kinase such as src or a transcription factor such as a cyclic AMP-response element-binding protein (CREB) or nervy. In some embodiments, the polypeptide is C3-ADP-ribosyltransferase, a dominant-negative RhoA mutant polypeptide, a cAMP-producing enzyme, glutamic acid decarboxylase, human proenkephalin, an inhibitor of a dominant-negative Vps24, an intestinal peptide (VIP), brain-derived neurotrophic factor (BDNF), neurotrophin-3 (NT-3), glial-derived neurotropic factor (GDNF), GAP 43, CAP23, a myc-tagged soluable adenylyl cyclase, a green fluorescent protein (GFP), a myristoylated GFP, a destabilized enhanced GFP (dEGFP), a myristoylated dEGFP, Cherry, or a myc-tagged Cherry. The polypeptide can be the dominant-negative RhoA mutant polypeptide is N19-RhoA polypeptide, a soluble adenylyl cyclase.

In some embodiments, the method further comprises contacting the axon with a brain-derived neurotrophic factor (BDNF), neurotrophin-3 (NT-3), glial-derived neurotropic factor (GDNF) or nerve growth factor.

The axon to which the methods of the invention can be applied is that of a sensory neuron, an upper motor neuron or a dorsal root ganglion. In some embodiments, the sensory neuron is a peripheral sensory neuron. In some embodiments, the virus is applied to the axon at the site of injury.

In one aspect, the invention provides a method of treating a condition in a mammal associated with aberrant axon function comprising administering to the mammal a virus or a composition of the invention. The virus or composition is can be administered locally to one or more selected axons. In some embodiments, the condition is axon injury associated with spinal cord injury, laceration, a stroke or multiple sclerosis. In some embodiments, the condition is axonal degeneration associated with axonal injury, diabetic peripheral neuropathy, neuropathic pain or inflammatory pain.

In one aspect, the invention provides an isolated mammalian neuron, the axon of which comprises a nucleic acid of the invention. As used herein, the term isolated in reference to an isolated neuron means that the neuron is not within the body of a mammal. In some embodiments, the mammalian neuron expresses a polypeptide encoded by the nucleic acid. The expressed polypeptide is one that modulates the growth or function of the axon of a mammalian neuron when it is expressed in the axon.

In one aspect, the invention provides a method for introducing an isolated nucleic acid into the axon of a neuron comprising contacting an alphavirus comprising the isolated nucleic acid with the axon. In some embodiments, the alphavirus is Sindbis virus or Semliki forest virus. In some embodiments, the nucleic acid is a nucleic acid of the invention.

Any feature or combination of features described herein are included within the scope of the present invention provided that the features included in any such combination are not mutually inconsistent as will be apparent from the context, this specification and the knowledge of one of ordinary skill in the art.

Methods and materials similar or equivalent to those described herein can be used to practice the invention. Suitable methods and materials are described below. These materials, methods, and examples are illustrative only and not intended to be limiting. All publications, patent applications, patents and other references mentioned herein are incorporated by reference in their entirety.

Other features and advantages of the invention will be apparent from the following detailed description and from the claims.

DESCRIPTION OF DRAWINGS

FIGS. 1A-O are data showing that the compartmentalization of DRGs enables axon-specific manipulations and quantitative measurement using fluorescent probes. (A) Immunofluorescence analysis of 3 DIV DRG cultures +/−5-FdU. Inclusion of 5-FdU effectively abolishes Schwann cell proliferation in DRG cultures. Scale bar, 50 μm. (B) Immunofluorescence analysis of 3 DIV DRG cultures demonstrates strong labeling of cell bodies and all projections with axon marker GAP43. Dendrite/cell body marker MAP2 is restricted to cell bodies, indicating the absence of MAP2-staining dendrites in DRG cultures and demonstrates that the neurites seen in axonal compartments are axons and not dendrites. Scale bar, 50 μm. (C) Immunofluorescence analysis of compartmented cultures (montage micrographs). Retrogradely labeled (WGA-Alexa555, red) DRG axons fasciculate and grow under the 1 mm divider into the axon compartment. Axons defasciculate as they enter the axon compartment. Cell bodies (DAPI, blue) are restricted to the cell body compartment. Only WGA-Alexa555 labeled cell bodies are included in data sets, as they comprise the population of neurons extending axons across the divider. (D) Dissociated DRG neurons (5 DIV) in compartmented cultures were treated with NGF in either or both compartments. NGF was capable of supporting DRG survival when applied to either axons or cell bodies individually, corroborating the presence of functional TrkA complexes throughout the developing neuron. Numbers on bars represent n cells per condition. (E, F) DRG axons in compartmented cultures were infected with a Sindbis virus encoding myr-dEGFP under the control of an IRES by applying the virus to both cell body and axonal compartments. Myr-dEGFP does not translocate from the site of its synthesis (Wu paper). Thus, the presence of fluorescence signal in the axon indicates that the protein was synthesized directly in the axon most likely as a result of viral application. Addition of cycloheximide or anisomycin for 48 hrs to the axonal compartment elicited a loss of myr-EGFP fluorescence in the axonal compartment, with no significant effect on myr-EGFP levels in the cell body compartment. All compartments were maintained in identical NGF-containing media throughout the course of the experiment. Scale bar, 50 μm (G) DIV3 E13 DRG neurons from CREB^(α/Δ +/−) mouse embryos demonstrated robust CREB mRNA FISH signal in axons, while neurons from CREB^(α/Δ +/−) embryos demonstrated an 86.3% loss of CREB mRNA FISH signal. Incomplete abolishment of FISH signals, relative to siRNA-treated axons, reflects residual alternatively-spliced CREBβ transcripts in these hypomorphic animals (Blendy et al., EMBO Journal 15, 1098-1106 (1996)). Additionally, axonal mRNAs are trafficked as mRNA-ribosome complexes, and impaired CREBβ mRNA-ribosome interactions due to the poor Kozak site (Blendy et al., EMBO Journal 15, 1098-1106 (1996)) in this transcript may lead to inefficient trafficking. Scale bar, 10 μm. (H) Quantification of data in (G). *p<0.0001. Numbers on bars represent n axons per condition. (I) Similar to the experiment in FIG. 4A, except equivalent numbers of cell bodies and axon terminals were used for Western blotting. DRG explants were cultured in Boyden chambers, and the upper compartment was incubated in 0 ng/ml NGF. The lower compartment was incubated in either 0 ng/ml NGF or 100 ng/ml NGF for 3 hours. Axon lysates (˜10⁴ cells) were prepared from the underside of the membrane and analysed by Western blot. As in FIG. 4A, only CREB was detected in axons, and CREB localization in 22 axons was dependent on NGF in the culture media. (J) DRG cultures were transfected with CREB siRNA and CREB levels were detected using a CREB antibody. Neurons transfected with nontargeting siRNA exhibited CREB immunoreactivity in axons, while neurons transfected with CREB specific siRNAs exhibited a near-complete abolishment of CREB immunoreactivity. Scale bar, 20 μm. (K) Quantification of data in (J). *p<0.001. Numbers on bars represent n axons per condition. (L) E15 DRG neuronal lysate (10 μg) was subjected to immunoblotting with the CST-9192 CREB antibody. (M) CREB was detected by immunofluorescence using CREB antibody sc-186 (see I, FIG. 4A, and Table S4). Scale bar 10 μm. (N) DIV3 E13 DRG neurons from CREB^(α/Δ +/−) embryos exhibited robust CREB immunoreactivity in axons, while neurons from CREB^(α/Δ +/−) embryos demonstrated an 84.8% loss of CREB IF signal. The greater degree of reduction in CREB immunofluorescence following siRNA treatment (see K) than in the CREB mutant mice likely reflects the more complete abolition of CREB following siRNA transfection than in the hypomorphic animal. Scale bar, 10 μm. (O) Quantification of data in (M). *p<0.0001. Numbers on bars represent n axons per condition.

FIGS. 2A-E are results showing that local protein synthesis in axons is required for NGF-dependent survival. (A) Phospho-4E-BP1 levels increase in growth cones in response to NGF treatment. DRG neurons were incubated with NGF-replete or NGF-free media; phospho-4E-BP1 levels in axons were measured by immunofluorescence. Scale bar, 50 μm. (B) Quantification of total and phospho-4EBP1 in (A) p=0.012. Numbers on bars represent n axons per condition. (C) Schematic diagram of compartmented (Campenot) chambers. E15 dissociated DRG neurons are cultured in the cell body compartment and axons grow under a thinly applied silicone grease layer that seals the chamber with the Permanox® plastic culture slide. (D) Application of protein synthesis inhibitors to axons blocks NGF-mediated retrograde survival. Dissociated DRG neurons were grown in compartmentalized chambers, and vehicle or NGF was added to the axon compartment. 1 μM cycloheximide (CHX) or 40 μM anisomycin (Aniso) were added to the axon compartment concurrently with NGF media. Cell body compartments were kept NGF-free during the course of the experiment. Cells crossing the divider were retrogradely labeled with WGA-Alexa555 and only WGA-positive cell bodies were counted in the data set. Survival was assessed by TUNEL assay. Examples of non-apoptotic and apoptotic are indicated with closed and open arrows, respectively (Blue=DAPI, Green=TUNEL). Scale bar, 20 μm. (E) Quantification of results from (D). *p<0.001. Numbers on bars represent n cells per condition.

FIGS. 3A-F are results showing that CREB mRNA and protein are localized to developing axons of DRG neurons. (A) Schematic diagram of Boyden chamber. DRGs were cultured in the centre of a glass coverslip placed on top of the microporous membrane. Axons grow across the coverslip and cross through the membrane by DIV4, when they are subjected to experimental conditions and mechanically harvested for analysis. (B) Fluorescent in situ hybridization (FISH) using riboprobes demonstrated the presence of CREB, but not cJun or STAT1 mRNA transcripts in axons. Insets show labeling in cell bodies of dissociated DRG neuron cultures at 10× magnification to demonstrate efficacy of riboprobes. Counterstained images show immunofluorescence using anti-GAP-43 antibody (Red). Scale bar, 10 μm. (C) Quantification of FISH data in (B). CREB levels were monitored with two separate probes (Table S1), and CREB levels were comparable to those of β-actin. Background FISH levels were defined as the average signal obtained using a scrambled β-actin riboprobe and subtracted from all other data. *p<0.001. Numbers on bars represent n axons per condition. (D) DRG neurons transfected with non-targeting siRNA demonstrated CREB mRNA FISH signals in axons, while neurons transfected with CREB-specific siRNA demonstrated a near-complete abolishment of CREB mRNA FISH signal. Scale bar, 10 μm. (E) Quantification of data in (D). *p<0.001. Numbers on bars represent n axons per condition. (F) CREB was detected in axonal lysates by RT-PCR using two separate primer pairs (Table S2). RT-PCR fidelity was assayed by concurrent RT-PCR from DRG cell body lysates.

FIGS. 4A-D are results showing that CREB is specifically translated in axons. (A) Selective localization and induction of CREB in distal axons. DRG explants were cultured in Boyden chambers (Wu et al, Nature 436, 1020-1024 (2005)) and the upper compartment was incubated in 0 ng/ml NGF. The lower compartment was incubated in either 0 ng/ml NGF or 100 ng/ml NGF for 3 hours. Lysates (25 μg protein) were prepared from the coverslip (cell body/proximal axon) or the underside of the membrane (distal axons) and analyzed by Western blot using an antibody that also recognizes CREB family members CREM and ATF-1. (B) NGF and protein synthesis are required for CREB localization in axon terminals. Axons were severed from DIV3 DRG explant cultures, and incubated with 0 or 100 ng/ml NGF, or 100 ng/ml NGF+1 μM cycloheximide (CHX) for 3 hours. CREB was detected by immunofluorescence (IF) using a CREB-specific antibody. Counter-staining shows immunofluorescence using anti-tau antibody (right). Scale bar, 50 μm. (C) Quantification of results in (B). *p<0.0001. Numbers on bars represent n axons per condition. (D) Low-power (20×) image of CREB immunofluorescence (IF) in DIV3 E15 DRGs. The majority of cellular CREB protein is associated with the nucleus, although signals are seen in the cytosol and axon. Scale bar 20 μm.

FIGS. 5A-C are results showing NGF-dependent translation of a CREB reporter mRNA in axons. (A) Schematic diagram of the Sindbis viral reporter construct used to monitor CREB translation. The reporter contains a myristoylated, destabilized EGFP (myr-dEGFP) with the 3′UTR of CREB, expressed under control of the Sindbis subgenomic promoter (PSG). (B) E15 DRG explant cultures were infected with Sindbis constructs expressing myr-dEGFP3′CREB on DIV3 and fluorescence (bottom panel) and phase (top panel) images, approximately 1000 μm from the cell body were collected after 24 hours. Fluorescence images are shown in inverted contrast in order to more readily visualize puncta. Scale bar, 25 μm. (C) myr-dEGFP_(3′CREB) puncta co-localize with ribosomal markers. myr-dEGFP_(3′CREB)-expressing axons were counter-stained by immunofluorescence using a ribosomal protein S6-specific antibody. EGFP fluorescence co-localizes with a population of S6-labeled ribosomal clusters. Scale bar, 10 μm.

FIGS. 6A-H are data showing that axonal CREB is specifically translated in response to NGF. (A) Schematic diagram of the Sindbis reporters construct used to monitor RhoA and histone H1f0 translation (Wu et al., Nature 436, 1020-1024 (2005)). The reporter contains a myristoylated, destabilised EGFP (dEGFP) with the 3′UTR of RhoA or histone H1f0, expressed under control of the Sindbis subgenomic promoter (P_(SG)). (B) E15 DRG explant cultures were infected with Sindbis constructs expressing _(myr-dEGFP) _(3′RhoA) or myr-dEGFP_(3′H1f0) on DIV3 and fluorescence images were collected after 24 h. Explants infected with myr-dEGFP_(3′RhoA) and cultured in the presence of NGF exhibited fluorescent puncta distributed throughout axons (0 h). Following replacement of the media with NGF-free media for 2 hours, puncta intensity was not significantly affected (2 hours). Explants infected with myr-dEGFP_(3′H1f0) and cultured in the presence of NGF did not exhibit fluorescent puncta in axons. Scale bar, 25 μm. (C) myr-dEGFP_(3′CREB)-infected axons were counterstained by immunofluorescence using antibodies specific to translational marker p-eIF4E, RNP associating protein Staufen, and mitochondrial marker VDAC/Porin1. myr-dEGFP was found in some, but not all ribosomal clusters (FIG. 5C), suggesting that myr-dEGFP-negative clusters are either translationally inactive, that they translate CREB mRNA in response to different stimuli, or that their function involves the translation of other mRNAs. Scale bar, 10 μm. (D) Axons from DIV3 DRGs were analyzed for CREB and mitochondrial localizations by immunofluorescence using CREB-specific and VDAC/porin1-specific antibodies. Scale bar, 10 μm. (E) Axons were severed from DIV3 DRG explant cultures, and incubated with 0 or 100 ng/ml NGF for 3 hours. CREB mRNA was detected by FISH using a CREB specific riboprobe. CREB mRNA levels did not significantly change during the course of the 23 experiments. Numbers on bars represent n axons per condition. (F) 40 μM LLnL was added to myrdEGFP_(3′CREB)-infected axons. Within 5 min, the eGFP fluorescence signal increased twofold, due to inhibition of proteasome-dependent degradation of the destabilized EGFP. Scale bar, 10 μm. (G) 3DIV dissociated DRGs were treated with NGF-free and NGF-replete media as in FIG. 7. CREB levels were assayed by immunofluorescence in contiguous axons: distal segments (450-500 μm), medial segments (250-300 μm) and proximal segments (50-100 μm) from the same axon were determined by their distances from the cell body. n≧10 axons per data point. *p<0.01. (H) Axons of DIV3 DRG explant cultures were analyzed by immunofluorescence for NGF effectors CREB, pTrkA and pErk5 at 3 DIV. Scale bar, 5 μm.

FIGS. 7A-B are results showing the axonal translation and retrograde transport of endogenous CREB. (A) CREB levels in severed axons of E15 DRGs were assayed by immunofluorescence with a CREB-specific antibody. CREB was depleted on removal of NGF, with near complete loss of fluorescence signals by 3 hours. Restoration of NGF resulted in a return of CREB to starting levels within 2 hours. Levels of GAP43 were not significantly affected by NGF removal or by restoration of NGF, indicating that changes in fluorescence intensity were not due to significant changes in axonal volume. Application of 1 μM cycloheximide or 40 μM anisomycin, concurrent with NGF replacement, prevented the restoration of CREB immunofluorescence, indicating that the NGF-dependent increase in CREB levels requires protein synthesis. The error bars represent s.e.m. (n=40). (B) CREB is depleted from axon terminals in a microtubule-dependent manner. CREB levels in severed axons were monitored, as in A, after removal and restoration of NGF, in the presence of LLnL or colchicine. Colchicine, but not LLnL, blocked the reduction in CREB levels following removal of NGF. The error bars represent s.e.m. (n=40).

FIGS. 8A-D are results showing the retrograde transport of a photoactivatable fluorescent CREB reporter protein. (A) E15 DRG explant cultures were infected with Sindbis constructs expressing Dendra or Dendra-CREB transcripts. Dendra and Dendra-CREB were visualized as green fluorescence (top panel), and growth cone-localized Dendra[-CREB] was photoactivated to its red form by 50 ms illumination of the boxed regions with a 408 nm laser. Movement of photoactivated Dendra signals was analyzed within the axon determined by green Dendra fluorescence mask. The leading edge (arrows) of red fluorescence for photoactivated Dendra-CREB was observed to move along the axon at a significantly faster rate than photoactivated Dendra. Photoactivated Dendra[-CREB] images are shown inverted in order to more readily visualize signals. Scale bar, 10 μm. (B) Quantification of data in (A). Grey line indicates the predicted diffusion rate of photoconverted Dendra-CREB, based on neuronal viscosity measurements (Bloodgood & Sabatini, Science 310, 866-869 (2005)). The expected diffusion rate of Dendra-CREB was calculated at various elapsed time points, using a previously measured diffusion coefficient (D) in neurons (Bloodgood & Sabatini, Science 310, 866-869 (2005)), in the formula x²=(2Dt), where x is the average displacement. No significant differences in axon diameter or morphology were observed between the neurons assayed. n≧20 axons per data point. *p<0.0001. (C) Dendra or Dendra-CREB was photoactivated by 1 s illumination of a 40 μm axon segment approximately 1 mm from its respective cell body and levels of photoactivated Dendra fluorescence were analyzed in the respective cell nucleus. Scale bar, 20 μm. (D) Quantification of data in (C). n=10 cells per data point. *p=0.0012.

FIGS. 9A-E are data showing that axonal CREB is required for CRE-dependent transcription and NGF-mediated DRG survival. (A) DRG axons in compartmented cultures were transfected with CREB siRNA in the axon compartment only, and CREB levels were detected using a CREB antibody. Axons crossing the compartment divider were retrogradely labeled with WGA-Alexa488. All compartments were maintained in NGF-containing media throughout the experiment. Scale bar, 50 μm. (B) Quantification of data in (A). Immunofluorescence levels in each compartment were normalized to fluorescence signals from cultures treated with non-targeting siRNA. *p<0.0001. Numbers on bars represent n axons per condition. (C) DRGs in compartmented cultures were incubated in NGF-free media, supplemented with BAF to suppress apoptosis. Axon compartments were treated with CREB-specific or non-targeting siRNA. After 48 hours, 30 ng/ml NGF was added to the axon compartment for 20 min, after which pCREB levels in nuclei were quantified by immunofluorescence. *p=0.0004. Numbers on bars represent n cells per condition. (D) DRGs in compartmented chambers were infected with adenovirus encoding luciferase under the control of a CRE transcriptional element and treated with NGF as in (C). *p<0.001. Numbers on bars represent n cells per condition. (E) E15 dissociated DRG were cultured in compartmented chambers as in FIG. 2C. NGF-induced neuronal survival at DIV7 was assayed following transfection of control or CREB-specific siRNA into the axon compartment at DIV5. *p<0.001. Numbers on bars represent n cells per condition.

FIGS. 10A-G are data showing selective CREB knockdown in distal axons, but not proximal axons determined by compartmentalized siRNA transfection. (A) Neurons transfected with CREB-specific siRNAs exhibited a specific abolishment of CREB mRNA FISH signal in the axon compartment (“Axon”), but no significant change in CREB mRNA FISH signals in proximal axons in the cell body compartment (“Cell Body”). (B) Quantification of data in (A). FISH levels in each compartment were normalized to fluorescence signals from cultures treated with non-targeting siRNA. β-actin mRNA FISH signals were unaffected by CREB-specific siRNA. *p<0.001. Numbers on bars represent n axons per condition. (C) Transfection was as in FIG. 9A, except CREB knockdown was assessed by Western blot instead of immunofluorescence. Lysates (10 μg protein) were prepared from the axon compartment of CREB-specific siRNA-treated compartmented cultures and analyzed by Western blot using a CREB-specific antibody. (D) DRGs in compartmented cultures (5 DIV) were incubated in NGF-free media, supplemented with BAF to prevent apoptosis. Axon compartments were transfected with CREB-specific or non-targeting siRNA. After 48 hours, 30 ng/ml NGF was added to the axon compartment for 20 min, after which cells were fixed and subjected to immunofluorescence analysis of nuclear pCREB. (E) DRGs in compartmented cultures were treated as in (D, FIG. 9A), after which pTrkA levels in nuclei were quantified by immunofluorescence. (F) DRGs in compartmented chambers were treated as in (D, E, FIG. 9A) and pErk5 levels in nuclei were quantified by immunofluorescence. (G) Dissociated DRG neurons (5 DIV) were infected with equal infectious units of recombinant CRE-luciferase adenovirus and incubated in various concentrations of NGF. After 24 hours, cells were fixed and analyzed by immunofluorescence for luciferase production. n=36 (0NGF), 29 (1 ng/ml NGF), 38 (5 ng/ml NGF), 29 (10 ng/ml NGF), 35 (20 ng/ml NGF), 35 (50 ng/ml NGF), 45 (100 ng/ml NGF) cells.

FIG. 11 is a schematic drawing illustrating local translation and retrograde transport of CREB mediates neuronal survival. (i) NGF binds to TrkA receptors causing dimerization and autophosphorylation. (ii) TrkA activation leads to translation of axonal CREB mRNA and (iii) the production of CREB protein. NGF-bound, activated TrkA receptors are internalized into endosomes and initiate formation of a signaling complex containing downstream effectors and the motor protein dynein. Axonally translated CREB protein associates with this NGF-pTrkA signaling endosome, which is required for downstream activation of CREB signaling in the cell body. (iv) CREB is retrogradely transported to the nucleus via microtubules and is phosphorylated at S 133 downstream of internalized TrkA signaling endosomes, via a kinase cascade including Mek5/Erk533. (v) Axonally-derived pCREB initiates the transcription of anti-apoptotic genes in the nucleus, leading to neuronal cell survival.

FIGS. 12A-D are results showing that the axons of embryonic day (E) 14 sensory neurons can express a virally-encoded protein. (A) Neurons from embryonic day (E) 14 sensory neurons were cultured in compartmentalized devices, and Sindbis-IRES virus expressing myc-sAC was applied exclusively to axons. Labeling in axons was shown with inverted contrast to facilitate visualization. Labeling was seen in axons, demonstrating expression of myc-sAC directly within the axon as a result of axon-specific viral application. Green staining in (B) shows the outline of axons. No myc labeling was seen in mock-treated axons (C). The outline of the axons in (C) is shown in (D).

FIGS. 13A-D are results showing that adult axons can express a potentially therapeutic protein. Rat postnatal sensory neurons harvested at 6 days after birth (P6) were cultured. At this age, the axons of these neurons have completed axonal pathfinding. Axons that have completed axonal pathfinding are thought to no longer contain ribosomes and to have reduced or absent capacity for protein synthesis. P6 neurons were grown in compartmentalized chambers, and a Sindbis IRES virus expressing a dominant negative (DN)-RhoA protein was applied exclusively to axons. As in FIG. 12, myc labeling was seen in axons (A) demonstrating that the virus led to the production of protein in axons. No labeling was seen in the cell body (A, inset) demonstrating that the virus was not trafficked back to the cell body, where myc-DN RhoA was synthesized and subsequently anterograde trafficked to the axon. (B) shows the outline of the axons. (C) & (D) are controls showing the absence of endogenous red labeling thereby establishing the specificity of the labeling seen in (A).

FIGS. 14A-C are results confirming that Sindbis-IRES viruses were not trafficked from the axon to the cell body where protein expression occurred. In (A), a Sindbis IRES virus expressing myc-Cherry was applied directly to cell bodies, resulting in clear myc-Cherry expression in the cell body. However, when the virus is applied to axons (B), the cell bodies do not express any myc-Cherry (although axons were expressing myc-Cherry, data not shown) demonstrating that expression in the axons did not occur by a process involving the virus being trafficked to the cell body, with subsequent expression of the transgene in the cell body. Background level of Cherry staining is shown in (C). Similarity of staining in (B) & (C) further demonstrates the absence of expression of the transgenes in the cell body in (B). The image is shown with inverted contrast so that red fluorescence appears black on a white background.

FIG. 15 is a schematic diagram of the structure of pSinRep5. An IRES sequence can be inserted into the pSinRep5 vector at the XbaI & MluI restriction sites to produce pSinRep5-IRES (FIG. 16).

FIG. 16 is a schematic diagram of pSinRep5-IRES.

FIG. 17 is the sequence of the region in pSinRep5-IRES (FIG. 16) that includes the IRES (shown in capital letters), restriction enzyme recognition sites (bolded), and the ATG start codon (underlined).

DETAILED DESCRIPTION OF THE INVENTION

The invention is based on the discovery that proteins can be expressed in the axons of a mammalian neuron. More specifically, the invention involves the discovery that a protein coding sequence operably linked to an internal ribosome entry site (IRES) in an RNA viral genome can be expressed in a mammalian axon when the RNA viral genome is transduced into the axon. Thus, the invention provides isolated recombinant nucleic acids such as DNA and RNA molecules, as well as RNA viruses that can be used to deliver selected polypeptide-coding sequences into the axons of mammalian neurons for expression of the encoded polypeptides in the axons. The invention also provides methods for expressing polypeptides in the axons of mammalian neurons, as well as methods of treating injured axons or treating conditions associated with aberrant axon function.

Nucleic Acids of the Invention

The invention provides isolated nucleic acids and viruses that can be used to deliver selected polypeptide-coding sequences into the axons of mammalian neurons for expression of the encoded polypeptides in the axons.

As used herein, the term “nucleic acid” refers to a polymer of deoxyribose nucleic acids (DNA), as well as ribose nucleic acids (RNA). The term includes linear molecules, as well as covalently closed circular molecules. It includes single stranded molecules, as well as double stranded molecules. The term “isolated” means that a select nucleic acid sequence is not contiguous with sequences that encode other genes or those involved in the expression of these other genes that flank the 5′ and 3′ ends of the select nucleic acid sequence in the naturally-occurring genome of the organism from which the select nucleic acid sequence is derived. An “isolated nucleic acid” has a structure that is different from that of any naturally occurring nucleic acid. The term “isolated nucleic acid” does not include nucleic acids present in mixtures of DNA molecules, transfected cells and cell clones such as in a cDNA or genomic DNA library.

A nucleic acid of the invention is also a recombinant molecule. As used herein, the term “recombinant” in reference to a nucleic acid means that the nucleic acid has a structure that is different from that of any naturally-occurring nucleic acid. A recombinant nucleic acid molecule is the product of the joining of at least two unrelated nucleic acid sequences using recombinant DNA techniques known to those of skill in the art such as described in MOLECULAR CLONING: A LABORATORY MANUAL, Sambrook & Russell eds., Cold Spring Harbor Laboratory Press, Cold Spring Harbor, N.Y. (2001) [hereinafter MOLECULAR CLONING] or CURRENT PROTOCOLS IN MOLECULAR BIOLOGY, eds. Ausubel et al., John Wiley & Sons, Inc. (1994) [hereinafter CURRENT PROTOCOLS]. Sequences are unrelated if they are derived from different sources. Non-limiting examples of different sources from which unrelated nucleic acids can be derived include different organisms, different species, or different isolates. Two sequences are also unrelated if they come from different regions within a larger naturally-occurring nucleic acid molecule. Discontinuous sequences, for example, are also unrelated. Thus, unrelated sequences include those that encode different genes or those involved in the expression of different genes, as well as those that do not immediately flank the 5′ and 3′ ends of a selected sequence in the naturally-occurring genome of the organism from which this sequence is obtained.

A recombinant nucleic acid of the invention can be (1) a linear or covalently-closed circular DNA plasmid or expression vector that is capable of replicating in a prokaryotic or eukaryotic host cell and has incorporated within a sequence encoding a selected mammalian polypeptide so that the plasmid or expression vector is not identical to any naturally-occurring plasmid or vector; (2) a nucleic acid incorporated into the genomic RNA of a virus or incorporated into the genome of a prokaryotic or eukaryotic host cell in a manner such that the resulting genome is not identical to any naturally-occurring genome; (3) a molecule such as a cDNA, a polyadenylyl RNA, a genomic fragment, a fragment produced by polymerase chain reaction (PCR), or a restriction fragment; and (4) an RNA molecule that has a viral packaging sequence, a translation initiation element, e.g. 5′ CAP or internal ribosome entry site, and a coding sequence for a mammalian protein operably-linked to the translation initiation element.

Thus, a recombinant nucleic acid of the invention can be a DNA or RNA molecule. A recombinant DNA molecule of the invention includes (1) a mammalian promoter; (2) an internal ribosome entry site (IRES) located 3′ of the promoter; (3) a selected polypeptide-coding sequence 3′ of the IRES, and (4) a viral packaging sequence. The polypeptide coding sequence can be operably linked to the IRES for expression of the polypeptide in the axon of a mammalian neuron. A recombinant RNA molecule of the invention includes (1) a translation initiation element; (2) a selected polypeptide-coding sequence and (3) a viral packaging sequence. The polypeptide coding sequence is operably-linked to the translation initiation element, which can be an IRES or a mammalian 5′ CAP. The recombinant RNA molecule can also have a 3′ polyadenylated tail.

As used herein, two components are “operably-linked” if they are linked in a manner that permits each component to function in its intended manner. When a polypeptide coding sequence and an IRES are operably-linked, the polypeptide coding sequence and the IRES are linked in such a way that, in the absence of an operably-linked 5′ CAP structure, the IRES functions to enable translation of the polypeptide coding sequence into a polypeptide when ribosomes, amino acids and other cellular components required for protein synthesis are present.

As used herein, the term “internal ribosome entry site” or “IRES” refers to a sequence within a nucleic acid molecule that is capable of recruiting ribosomes for initiation of protein translation from a polypeptide coding sequence. IRES can promote translation from any polypeptide coding sequence that is downstream of the IRES sequence. Generally, IRES's can be found in the 5′ untranslated regions of polypeptide-coding sequences and allow translation of the RNA in a 5′CAP-independent manner. In a recombinant RNA molecule of the invention, the IRES can be within the 5′ untranslated region of the RNA molecule or it can be inserted into different parts of the RNA molecule as long as it is located 5′ of a polypeptide coding sequence. The IRES can be less than 10 nucleotides upstream or 5′ of the start codon of a coding sequence that is operably linked to it, or it can be as distant as 200 to 300 nucleotides or more upstream of the first start codon of a coding sequence that is operably linked to it.

IRES can be found in viral RNA genomes, as well as in sequences from eukaryotic origin. Non-limiting examples of viral IRES sequences include those found in: (1) picornaviruses, e.g., poliovirus (PV) or the human enterovirus 71, e.g. strains 74231MS187 and BrCr thereof; (2) encephalomyocarditis virus (EMCV); (3) foot-and-mouth disease virus (FMDV); (4) flaviviruses, e.g., hepatitis C virus (HCV); (5) pestiviruses, e.g., classical swine fever virus (CSFV); (6) retroviruses, e.g., murine leukemia virus (MLV); and (7) lentiviruses, e.g., simian immunodeficiency virus (SIV).

Non-limiting examples of non-viral IRES sequences can be found in cellular mRNA such as those encoding (1) translation initiation factors, e.g., eIF4G or DAP5; (2) transcription factors, e.g., c-Myc (Yang and Sarnow, Nucleic Acids Research 25: 2800-2807 (1997)) or NF-KB-repressing factor (NRF); (3) growth factors, e.g., vascular endothelial growth factor (VEGF), fibroblast growth factor (FGF-2) and platelet-derived growth factor B (PDGF B); (4) homeotic genes, e.g., Antennapedia; (5) survival proteins, e.g., X-linked inhibitor of apoptosis (XIAP) or Apaf-1; and (6) chaperones, e.g., immunoglobulin heavy-chain binding protein BiP (Martinez-Salas et al., Journal of General Virology 82: 973-984, (2001)). IRES can also be found in plant viral sequences. Any IRES now known or later identified can be used to practice the invention.

Non-limiting examples of IRES sequences can be found in the following viral sequences: encephalomyocarditis virus (EMCV. GenBank accession #NC001479), cricket paralysis virus (GenBank accession #AF218039), Drosophila C virus (GenBank accession #AFO14388), Plautia stali intestine virus (GenBank accession #AB006531), Rhopalosiphum padi virus (GenBank accession #AF022937), Himetobi P virus (GenBank accession #AB017037), acute bee paralysis virus (GenBank accession #AF1 50629), Black queen cell virus (GenBank accession #AF183905), Triatoma virus (GenBank accession #AF178440), Acyrthosiphon pisum virus (GenBank accession #AF024514), infectious flacherie virus (GenBank accession #AB000906), and/or Sacbrood virus (Genbank accession #AF092924).

Additional examples of IRES sequences are provided in A Bioinformatical Approach to the Analysis of Viral and Cellular Internal Ribosome Entry Sites in NEW MESSENGER RNA RESEARCH COMMUNICATIONS 133-166, Nova Science Publishers, Hauppauge, N.Y. (2007). See also http://www.iresite.org.

An IRES sequence can also be a synthetic sequence that has been designed to mimic the function of naturally occurring IRES sequences according to methods know in the art. See, for example, Chappell et al. Proc Natl Acad Sci USA. 97:1536-41 (2000).

An example of an IRES sequence is the following:

(SEQ ID NO: 29) 1 GCCCCTCTCC CTCCCCCCCC CCTAACGTTA CTGGCCGAAG 41 CCGCTTGGAA TAAGGCCGGT GTGCGTTTGT CTATATGTTA 81 TTTTCCACCA TATTGCCGTC TTTTGGCAAT GTGAGGGCCC 121 GGAAACCTGG CCCTGTCTTC TTGACGAGCA TTCCTAGGGG 161 TCTTTCCCCT CTCGCCAAAG GAATGCAAGG TCTGTTGAAT 201 GTCGTGAAGG AAGCAGTTCC TCTGGAAGCT TCTTGAAGAC 241 AAACAACGTC TGTAGCGACC CTTTGCAGGC AGCGGAACCC 281 CCCACCTGGC GACAGGTGCC TCTGCGGCCA AAAGCCACGT 321 GTATAAGATA CACCTGCAAA GGCGGCACAA CCCCAGTGCC 361 ACGTTGTGAG TTGGATAGTT GTGGAAAGAG TCAAATGGCT 401 CTCCTCAAGC GTATTCAACA AGGGGCTGAA GGATGCCCAG 441 AAGGTACCCC ATTGTATGGG ATCTGATCTG GGGCCTCGGT 481 GCACATGCTT TACATGTGTT TAGTCGAGGT TAAAAAAACG 521 TCTAGGCCCC CCGAACCACG GGGACGTGGT TTTCCTTTGA 561 AAAACACGAT GATAAGCTTG CCACA

Additional examples of IRES sequences are shown below.

From Hepatitis A virus (CF53), partial 5′ nontranslated region (Genbank accession no: M63025)

(SEQ ID NO: 30) GTTTGCCTAGGCTATAGGCTATTTCTCCCCTTCCCTT TTCCCTGTTTTGTGTAAATATTAATTCCTGCAGGTTC AGGGTTCTTTAATCTGTTTCTCTATAAGAACACTCAT TTTCACGCTTTCTGTCTGCTTTCTTCCAGGGCTCTCC CCTTGCCCTAGGCTCTGGCCGTTGCGCCCGGCGGGGT CAACTCCATGATTAGCATGGAGCTGTAGGAGTCTAAA TTGGGGACGCAGATGTTTGGGACGTCACCTTGCAGTA TTAACTTGGCTCTCATGAAGCTCTTTGATCTTCCACA AGAGGTAGGCTACGGGTGAAACCTCTTAAGCTAGTAC TTCTATGAAGAGATGCTTTGGATAGGGTAACAGCGGC GGATATTGGTGAGTTGTTAAGACAAAAACCTTTCAAC GCCGGAGGACTGGCTCTCATCCAGTGGATGCATTGAG TGGATTGTTTGTCAGGGCTGTCTCTAGGCTTAATCTC AGACCTCTCTGTGCTTAGGGCAAACATTACTTGGCCT TAAATGGGATTCTGTGAGAGGGGATCCCTCCATTGAT AGCTGGACTTTTCTTTGGGGCCTTAGGTGGTGTTTGC CTCTGAGGTACTCAGGGGCATTTAGGTTTTTCCTCAC TCTCAAATAACTATGAATATGTCTAG

From human T-cell lymphotropic virus type 1 BCI1-2 long terminal repeat region (U32552):

(SEQ ID NO: 31) GGGGAGTTAGAGCCTCCCAGTGAAAAACATTTCCGCG AAACAGAAGTCTGAAAAGGTCAGGGCCCAGACTAAGG CTCTGACGTCTCCCCCCGGAGGGACAGCTCAGCACCG GCTCAGGCTAGGCCCTGACGTGTCCCCCTGAAGACAA ATCATAAGCTCAGACCTCCGGGAAGCCACCGGAACCA CCCATTTCCTCCCCATGTTTGTCGAGCCGCCCTCAGG CGTTGACGACAACCCCTCACCTCAAAAAACTTTTCAT GGCACGCATATGGCTGAATAAACTAACAGGAGTCTAT AAAAGCGTGGAGACAGTTCAGGAGGGGGCTCGCATCT CTCCTTCACGCGCCCGCCGCCCTACCTGAGGCCGCCA TCCACGCCGGTTGAGTCGCGTTCTGCCGCCTCCCGCC TGTGGTGCCTCCTGAACTGCGTCCGCCGTCTAGGTAA GTTTAGAGCTCAGGTCGAGACCGGGCCTTTGTCCGGC GCTCCCTTGGAGCCTACCTAGACTCAGCCGGCTCTCC ACGCTTTGCCTGACCCTGCTTGCTCAACTCTGCGTCT TTGTTTCGTTTTCTGTTCTGCGCCGCTACAGATCGAA AGTTCCACCCCTTTCCCTTTCATTCACGACTGACTGC CGGCTTGGCCCACGGCCAAGTACCGGCGACTCCGTTG GCTCGGAGCCAGCGACAGCCCATTCTA

From hog cholera virus (Classical swine fever virus) “Chinese” strain (C-strain; EP 0 351 901 B1) encoding polyprotein (Z46258):

(SEQ ID NO: 32) GTATACGAGGTTAGTTCATTCTCGTATACACGATTGG ACAAATCAAAATTATAATTTGGTTCAGGGCCTCCCTC CAGCGACGGCCGAACTGGGCTAGCCATGCCCATAGTA GGACTAGCAAAACGGAGGGACTAGCCATAGTGGCGAG CTCCCTGGGTGGTCTAAGTCCTGAGTACAGGACAGTC GTCAGTAGTTCGACGTGAGCAGAAGCCCACCTCGAGA TGCTACGTGGACGAGGGCATGCCAAGACACACCTTAA CCCTAGCGGGGGTCGCTAGGGTGAAATCACACCACGT GATGGGAGTACGACCTGATAGGGCGCTGCAGAGGCCC ACTATTAGGCTAGTATAAAAATCTCTGCTGTACATGG CAC

From Equine rhinitis A virus, nt 1-881 (NC_(—)003982)

(SEQ ID NO: 33) TTAATTAAAAGTTGAACCTGTAGCGTCAGTAAAACGC AGTAACCGCAAGCAATTGCCTGTAGCGTCAGTAAAAC GCAATACACAAGATTTGAGCCTGTAGCGTCAGTAAAA CGCTGCAACCACAAGCTATTGACTGTAGCGTCAGTAA AACGCAAACATTCTTGTGGCGCTCGCGTAGCGCTCAA GTGCAGAGCTTCCCGGCTTTAAGGGTTACTGCTCGTA ATGAGAGCACATGACATTTTGCCAAGATTTCCTAGCA ATTGTCACGGGAGAGAGGAGCCCGTTCTCGGGCACTT TTCTCTCAAACAATGTTGGCGCGCCTCGGCGCGCCCC CCCTTTTTCAGCCCCCTGTCATTGACTGGTCGAAGGC GCTCGCAATAAGACTGGTCGTTGCTTGGCTTTTCTAT TGTTTCAGGCTTTAGCGCGCCCTTGCGCGGCGGGCCG TCAAGCCCGTGTGCTGTACAGCACCAGGTAACCGGAC AGCGGCTTGCTGGATTTTCCCGGTGCCATTGCTCTGG ATGGTGTCACCAAGCTGGCAGATGCGGAGTGAACCTT ACGAAGCGACACACCTGTGGTAGCGCTGCCCAGAAGG GAGCGGAGCTCCCCCGCCGCGAGGCGGTCCTCTCTGG CCAAAAGCCCAGCGTTAATAGCGCCTTCTGGGATGCA GGAACCCCACCTGCCAGGTGTGAAGTGGACTAAGTGG ATCTCCAATTTGGCCTGTTCTGAACTACACCATCTAC TGCTGTGAAGAATGTCCTGAAGGCAAGCTGGTTACAG CCCTGATCAGGAGCCCCGCTCGTGACTCTCGATCGAC GCGGGGTCAAAAACTGTCTAAGCAGCAGCAGAAACGC GGGAGCGTTTCTTTTTCCTTATTTGTTTCA

From c-myc 5′ UTR IRES 407 nts

(SEQ ID NO: 34) CAGGATCCCCCTAATTCCAGCGAGAGGCAGAGGGAGC GAGCGGGCGGCCGGCTAGGGTGGAAGAGCCGGGCGAG CAGAGCTGCGCTGCGGGCGTCCTGGGAAGGGAGATCC GGAGCGAATAGGGGGCTTCGCCTCTGGCCCAGCCCTC CCGCTGATCCCCCAGCCAGCGGTCCGCAACCCTTGCC GCATCCACGAAACTTTGCCCATAGCAGCGGGCGGGCA CTTTGCACTGGAACTTACAACACCCGAGCAAGGACGC GACTCTCCCGACGCGGGGAGGCTATTCTGCCCATTTG GGGACACTTCCCCGCCGCTGCCAGGACCCGCTTCTCT GAAAGGCTCTCCTTGCAGCTGCTTAGACGCTGGATTT TTTTCGGGTAGTGGAAAACCAGCAGCCTCCCGCGACC ATG

From Bovine enterovirus, nt 1-819 (NC_(—)001859)

(SEQ ID NO: 35) TTAAAACAGCCTGGGGGTTGTACCCACCCCTGGGGCC CACGTGGCGCTAGTACTCTGGTTCGTTAGAACCTTTG TACGCCTGTTTTCCCCTCCTTAAACAAATTAAGATCT CTGCCAATGTGGGGAGTAGTCCGACTCCGCACCGATA CGTCGCACCAGTAGACCGGTTCGCTTAGGACCCTTCT ACGGATTGGTATGAGTTCCCCACCCCGTAACTTAGAA GTACTAGCAAAACCGACCAATAGGAGCGTGGCACCCA GCTGCGTTAAGGTCAAGCACTTCTGTCTCCCCGGCCA GAAATGGTCGTCACCCGCCCTCTCTACTACGAGAAGC CTATTAACCATTGAAGGCGATGAGGAGTTGCGCTCCA CCACAACCCCAGTGGTAGCTCTGAGAGATGGGGCTCG CAGTCACCCCCGTGGTAACACGGTTGCTTGCCCGCGT GTGCTCTCGGGTTCGGCCACTTGGCCGTTCACTCCAA CTCGTTGTAAGTGGCCAAGAGCCTATTGTGCTAGAGA GGTTTTCCTCCGGAGCCGTGAATGCTGCTAATCCCAA CCTCCGAGCGTGTGCGCACAATCCAGTGTTGCTACGT CGTAACGCGCAAGTTGGAGGCGGAACAGACTACTTTC GGTACTCCGTGTTTCCTTATTATTTTATACAACAATT TATGGTGACATTGACTGATACTATTGAGTTCGCCCGC TTGCCATTGAATATTGCCTTGTATTACCTTATAGCAT TTCAAAAAGCCACAGATCTCACCCTCGAGCTCATTCA CTTTGCAGTTTGTTTGAATCGCATACACAAGACATTT GAACA

As used herein, the term “5′ CAP” refers to a nucleotide on the 5′ terminus of an RNA molecule that includes a polypeptide coding sequence. The 5′CAP can promote initiation of protein translation from the polypeptide coding sequence if the polypeptide coding sequence is operably-linked to the 5′ CAP. Structurally, the 5′ CAP includes a guanine nucleotide covalently linked to the 5′ terminus of an RNA molecule via a 5′ to 5′ triphosphate linkage. The guanine nucleotide is methylated on the 7 position.

The viral packaging sequence is a sequence in the nucleic acid molecule, e.g. viral RNA, that interacts with a viral capsid protein and is required for encapsidation of the RNA molecule during the formation of viral particles. Viral packaging sequences are known to those of skill in the art. See, for example, Frolova et al., Journal of Virology 71: 248-258 (1997).

A recombinant RNA molecule of the invention can be a single, positive- or negative-stranded RNA viral genome that has a coding sequence for a selected polypeptide. The coding sequence is operably-linked to an IRES sequence or a 5′ CAP. Where the viral genome is a negative strand RNA sequence, the polypeptide coding region and IRES sequence are sense sequences in order for translation to occur. A recombinant RNA molecule of the invention can also be an engineered RNA sequence that includes: (1) a coding sequence for the selected polypeptide operably-linked to an IRES sequence or 5′ CAP and (2) a viral packaging sequence sufficient for packaging of the RNA expression vector into viral particles.

A recombinant DNA molecule of the invention can be a double stranded expression vector that has a sequence encoding an RNA molecule of the invention, i.e. the expression vector can function as a template from which an RNA molecule of the invention can be transcribed. The recombinant DNA molecule can be a plasmid vector that has a bacterial or mammalian origin of replication, as well as sequences that encode the recombinant RNA molecules of the invention. Recombinant DNA molecules of the invention can serve as a template for the production of RNA molecules of the invention either by in vitro transcription or in vivo expression in an appropriate host cell.

The selected polypeptide encoded by recombinant nucleic acids of the invention can be any polypeptide that can affect the growth or function of the axon of a mammalian neuron. Examples of these polypeptides include, without limitation, the bacterial toxin C3-ADP-ribosyltransferase that is useful for inhibiting the small GTPase RhoA; dominant-negative RhoA mutants, for example, N19-RhoA; dominant-negative RhoA kinase (ROCK) mutants, for example, ROCK 11009A described by Ishizaki et al., FEBS Lett. 404:118-124 (1997); a cyclic AMP-producing enzyme such as the soluble adenylyl cyclase (sAC) described by Wu et al., Nat. Neurosci. 9:1257-64 (2006); glutamic acid decarboxylase (GAD), an enzyme that synthesizes the neurotransmitter gamma-aminobutyric acid (GABA), which suppresses activity in nerve cells (Hao et al., Annals of Neurology, 57: 914-918, (2005)); human proenkephalin, an endogenous opioid peptide with antihyperalgesic properties (Wilson, et al., PNAS, 96: 3211-3216, 1999); the dominant-negative Vps24 required for HSV envelopment (Crump et al., J. Virol. 81:7380-7387, 2007); GAP43, a gene product of a neuronal regeneration-associated gene and regulator of developmental growth cone motility; CAP23, an activator of intrinsic growth capacity in dorsal root ganglion neurons; Brain-Derived Neurotrophic Factor (BDNF), a neurotrophic factor in the brain and the periphery that act on certain neurons of the central and peripheral nervous systems and helps to support the survival or existing neurons and encourage the growth and differentiation of new neurons and synapses; Neurotrophin-3 (NT-3), a neurotrophic factor in the nerve growth factor family of neurotropins, i.e. a protein growth factor that acts on the nerves of the central and peripheral nervous systems and helps to support the survival and differentiation of existing neurons and encourages the growth and differentiation of new neurons and synapses; and glial-derived neurotropic factor (GDNF), a small protein that promotes survival of neurons, especially dopamiergic and motoneurons. See also U.S. Patent Application No. 2003/0118557.

An example of a C3-ADP-ribosyltransferase sequence is provided by Genbank M74038 and shown below:

(SEQ ID NO: 36) MKGIRKSILCLVLSAGVIAPVTTSIVQSPQKCYACTVDKGSYADTF TEFTNVEEAKKWGNAQYKKYGLSKPEQEAIKFYTRDASKINGPLRA NQGNENGLPADILQKVKLIDQSFSKMKMPQNIILFRGDDPAYLGPE FQDKILNKDGTINKTVFEQVKAKFLKKDRTEYGYISTSLMSAQFGG RPIVTKFKVTNGSKGGYIDPISYFPGQLEVLLPRNNSYYISDMQIS PNNRQIMITAMIFK

The sequence of human N19-RhoA, an example of a dominant-negative RhoA mutant is provided by Genbank NM_(—)001664 and shown below:

(SEQ ID NO: 37) MAAIRKKLVIVGDGACGKNCLLIVFSKDQFPEVYVPTVFENYVADI EVDGKQVELALWDTAGQEDYDRLRPLSYPDTDVILMCFSIDSPDSL ENIPEKWTPEVKHFCPNVPIILVGNKKDLRNDEHTRRELAKMKQEP VKPEEGRDMANRIGAFGYMECSAKTKDGVREVFEMATRAALQARRG KKKSGCLVL

An example of a dominant-negative RhoA kinase (ROCK) is provided by Genbank NM_(—)005406 and shown below:

(SEQ ID NO: 38) MSTGDSFETRFEKMDNLLRDPKSEVNSDCLLDGLDALVYDLDFPAL RKNKNIDNFLSRYKDTINKIRDLRMKAEDYEVVKVIGRGAFGEVQL VRHKSTRKVYAMKLLSKFEMIKRSDSAFFWEERDIMAFANSPWVVQ LFYAFQDDRYLYMVMEYMPGGDLVNLMSNYDVPEKWARFYTAEVVL ALDAIHSMGFIHRDVKPDNMLLDKSGHLKLADFGTCMKMNKEGMVR CDTAVGTPDYISPEVLKSQGGDGYYGRECDWWSVGVFLYEMLVGDT PFYADSLVGTYSKIMNHKNSLTFPDDNDISKEAKNLICAFLTDREV RLGRNGVEEIKRHLFFKNDQWAWETLRDTVAPVVPDLSSDIDTSNF DDLEEDKGEEETFPIPKAFVGNQLPFVGFTYYSNRRYLSSANPNDN RTSSNADKSLQESLQKTIYKLEEQLHNEMQLKDEMEQKCRTSNIKL DKIMKELDEEGNQRRNLESTVSQIEKEKMLLQHRINEYQRKAEQEN EKRRNVENEVSTLKDQLEDLKKVSQNSQLANEKLSQLQKQLEEAND LLRTESDTAVRLRKSHTEMSKSISQLESLNRELQERNRILENSKSQ TDKDYYQLQAILEAERRDRGHDSEMIGDLQARITSLQEEVKHLKHN LEKVEGERKEAQDMLNHSEKEKNNLEIDLNYKLKSLQQRLEQEVNE HKVTKARLTDKHQSIEEAKSVAMCEMEKKLKEEREAREKAENRVVQ IEKQCSMLDVDLKQSQQKLEHLTGNKERMEDEVKNLTLQLEQESNK RLLLQNELKTQAFEADNLKGLEKQMKQEINTLLEAKRLLEFELAQL TKQYRGNEGQMRELQDQLEAEQYFSTLYKTQVKELKEEIEEKNREN LKKIQELQNEKETLATQLDLAETKAESEQLARGLLEEQYFELTQES KKAASRNRQEITDKDHTVSRLEEANSMLTKDIEILRRENEELTEKM KKAEEEYKLEKEEEISNLKAAFEKNINTERTLKTQAVNKLAEIMNR KDFKIDRKKANTQDLRKKEKENRKLQLELNQEREKFNQMVVKHQKE LNDMQAQLVEECAHRNELQMQLASKESDIEQLRAKLLDLSDSTSVA SFPSADETDGNLPESRIEGWLSVPNRGNIKRYGWKKQYVVVSSKKI LFYNDEQDKEQSNPSMVLDIDKLFHVRPVTQGDVYRAETEEIPKIF QILYANEGECRKDVEMEPVQQAEKTNFQNHKGHEFIPTLYHFPANC DACAKPLWHVFKPPPALECRRCHVKCHRDHLDKKEDLICPCKVSYD VTSARDMLLLACSQDEQKKWVTHLVKKIPKNPPSGFVRASPRTLST RSTANQSFRKVVKNTSGKTS

An example of a soluble adenylyl cyclase sequence is provided by Genbank NM_(—)018417 and shown below:

(SEQ ID NO: 39) MNTPKEEFQDWPIVRIAAHLPDLIVYGHFSPERPFMDYFDGVLMFV DISGFTAMTEKFSSAMYMDRGAEQLVEILNYHISAIVEKVLIFGGD ILKFAGDALLALWRVERKQLKNIITVVIKCSLEIHGLFETQEWEEG LDIRVKIGLAAGHISMLVFGDETHSHFLVIGQAVDDVRLAQNMAQM NDVILSPNCWQLCDRSMIEIESVPDQRAVKVNFLKPPPNFNFDEFF TKCTTFMHYYPSGEHKNLLRLACTLKPDPELEMSLQKYVMESILKQ IDNKQLQGYLSELRPVTIVFVNLMFEDQDKAEEIGPAIQDAYMHIT SVLKIFQGQINKVFMFDKGCSFLCVFGFPGEKVPDELTHALECAMD IFDFCSQVHKIQTVSIGVASGIVFCGIVGHTVRHEYTVIGQKVNLA ARMMMYYPGIVTCDSVTYNGSNLPAYFFKELPKKVMKGVADSGPLY QYWGRTEKVMFGMACLICNRKEDYPLLGRNKEINYFMYTMKKFLIS NSSQVLMYEGLPGYGKSQILMKIEYLAQGKNHRIIAISLNKISFHQ TFYTIQMFMANVLGLDTCKHYKERQTNLRNKVMTLLDEKFYCLLND IFHVQFPISREISRMSTLKKQKQLEILFMKILKLIVKEERIIFIID EAQFVDSTSWRFMEKLIRTLPIFIIMSLCPFVNIPCAAARAVIKNR NTTYIVIGAVQPNDISNKICLDLNVSCISKELDSYLGEGSCGIPFY CEELLKNLEHHEVLVFQQTESEEKTNRTWNNLFKYSIKLTEKLNMV TLHSDKESEEVCHLTSGVRLKNLSPPTSLKEISLIQLDSMRLSHQM LVRCAAIIGLTFTTELLFEILPCWNMKMMIKTLATLVESNIFYCFR NGKELQKALKQNDPSFEVHYRSLSLKPSEGMDHGEEEQLRELENEV IECHRIRFCNPMMQKTAYELWLKDQRKAMHLKCARFLEEDAHRCDH CRGRDFIPYHHFTVNIRLNALDMDAIKKMAMSHGFKTEEKLILSNS EIPETSAFFPENRSPEEIREKILNFFDHVLTKMKTSDEDIIPLESC QCEEILEIVILPLAHHFLALGENDKALYYFLEIASAYLIFCDNYMA YMYLNEGQKLLKTLKKDKSWSQTFESATFYSLKGEVCFNMGQIVLA KKMLRKALKLLNRIFPYNLISLFLHIHVEKNRHFHYVNRQAQESPP PGKKRLAQLYRQTVCLSLLWRIYSYSYLFHCKYYAHLAVMMQMNTA LETQNCFQIIKAYLDYSLYHHLAGYKGVWFKYEVMAMEHIFNLPLK GEGIEIVAYVAETLVFNKLIMGHLDLAIELGSRALQMWALLQNPNR HYQSLCRLSRCLLLNSRYPQLIQVLGRLWELSVTQEHIFSKAFFYF VCLDILLYSGFVYRTFEECLEFIHQYENNRILKFHSGLLLGLYSSV AIWYARLQEWDNFYKFSNRAKNLLPRRTMTLTYYDGISRYMEGQVL HLQKQIKEQSENAQASGEELLKNLENLVAQNTTGPVFCPRLYHLMA YVCILMGDGQKCGLFLNTALRLSETQGNILEKCWLNMNKESWYSTS ELKEDQWLQTILSLPSWEKIVAGRVNIQDLQKNKFLMRANTVDNHF

An example of a glutamic acid decarboxylase (GAD) is provided by Genbank NM_(—)000817 and shown below:

(SEQ ID NO: 40) MASSTPSSSATSSNAGADPNTTNLRPTTYDTWCGVAHGCTRKLGLK ICGFLQRTNSLEEKSRLVSAFKERQSSKNLLSCENSDRDARFRRTE TDFSNLFARDLLPAKNGEEQTVQFLLEVVDILLNYVRKTFDRSTKV LDFHHPHQLLEGMEGFNLELSDHPESLEQILVDCRDTLKYGVRTGH PRFFNQLSTGLDIIGLAGEWLTSTANTNMFTYEIAPVFVLMEQITL KKMREIVGWSSKDGDGIFSPGGAISNMYSIMAARYKYFPEVKTKGM AAVPKLVLFTSEQSHYSIKKAGAALGFGTDNVILIKCNERGKIIPA DFEAKILEAKQKGYVPFYVNATAGTTVYGAFDPIQEIADICEKYNL WLHVDAAWGGGLLMSRKHRHKLNGIERANSVTWNPHKMMGVLLQCS AILVKEKGILQGCNQMCAGYLFQPDKQYDVSYDTGDKAIQCGRHVD IFKFWLMWKAKGTVGFENQINKCLELAEYLYAKIKNREEFEMVFNG EPEHTNVCFWYIPQSLRGVPDSPQRREKLHKVAPKIKALMMESGTT MVGYQPQGDKANFFRMVISNPAATQSDIDFLIEEIERLGQDL

An example of human proenkephalin is provided by Genbank NM_(—)006211 and shown below:

(SEQ ID NO: 41) MARFLTLCTWLLLLGPGLLATVRAECSQDCATCSYRLVRPADINFL ACVMECEGKLPSLKIWETCKELLQLSKPELPQDGTSTLRENSKPEE SHLLAKRYGGFMKRYGGFMKKMDELYPMEPEEEANGSEILAKRYGG FMKKDAEEDDSLANSSDLLKELLETGDNRERSHHQDGSDNEEEVSK RYGGFMRGLKRSPQLEDEAKELQKRYGGFMRRVGRPEWWMDYQKRY GGFLKRFAEALPSDEEGESYSKEVPEMEKRYGGFMRF

An example of a dominant-negative Vps24 sequence is provided by Genbank NM_(—)016079 and shown below:

(SEQ ID NO: 42) MGLFGKTQEKPPKELVNEWSLKIRKEMRVVDRQIRDIQREEEKVKR SVKDAAKKGQKDVCIVLAKEMIRSRKAVSKLYASKAHMNSVLMGMK NQLAVLRVAGSLQKSTEVMKAMQSLVKIPEIQATMRELSKEMMKAG IIEEMLEDTFESMDDQEEMEEEAEMEIDRILFEITAGALGKAPSKV TDALPEPEPPGAMAASEDEEEEEEALEAMQSRLATLRS

An example of a GAP43 sequence is provided by Genbank NM_(—)002045 and shown below:

(SEQ ID NO: 43) MLCCMRRTKQVEKNDDDQKIEQDGIKPEDKAHKAATKIQASFRGHI TRKKLKGEKKDDVQAAEAEANKKDEAPVADGVEKKGEGTTTAEAAP ATGSKPDEPGKAGETPSEEKKGEGDAATEQAAPQAPASSEEKAGSA ETESATKASTDNSPSSKAEDAPAKEEPKQADVPAAVTAAAATTPAA EDAAAKATAQPPTETGESSQAEENIEAVDETKPKESARQDEGKEEE PEADQEHA

An example of a CAP23 sequence is provided by Genbank NM_(—)006317 and shown below:

(SEQ ID NO: 44) MGGKLSKKKKGYNVNDEKAKEKDKKAEGAATEEEGTPKESEPQAAA EPAEAKEGKEKPDQDAEGKAEEKEGEKDAAAAKEEAPKAEPEKTEG AAEAKAEPPKAPEQEQAAPGPAAGGEAPKAAEAAAAPAESAAPAAG EEPSKEEGEPKKTEAPAAPAAQETKSDGAPASDSKPGSSEAAPSSK ETPAATEAPSSTPKAQGPAASAEEPKPVEAPAANSDQTVTVKE

An example of a brain-derived neurotrophic factor (BDNF) are provided by Genbank CAA62632 and shown below:

(SEQ ID NO: 45) MTILFLTMVISYFGCMKAAPMKEANIRGQGGLAYPGVRTHGTLESV NGPKAGSRGLTSLADTFEHVIEELLDEDHKVRPNEENNKDADLYTS RVMLSSQVPLEPPLLFLLEEYKNYLDAANMSMMVLRHSDPARRGEL SVCDSISEWVTAADKKTAVDMSGGTVTVLEKVPVSKGQLKQYFYET KCNPMGYTKEGCRGIDKRHWNSQCRTTQSYVRALTMDSKKRIGWRF IRIDTSCVCTLTIKRGR

Examples of neurotrophin-3 (NT-3) are provided by Genbank AAI07076 & and shown below:

(SEQ ID NO: 46) MSILFYVIFLAYLRGIQGNNMDQRSLPEDSLNSLIIKLIQADILKN KLSKQMVDVKENYQSTLPKAEAPREPERGGPAKSAFQPVIAMDTEL LRQQRRYNSPRVLLSDSTPLEPPPLYLMEDYVGSPVVANRTSRRKR YAEHKSHRGEYSVCDSESLWVTDKSSAIDIRGHQVTVLGEIKTGNS PVKQYFYETRCKEARPVKNGCRGIDDKHWNSQCKTSQTYVRALTSE NNKLVGWRWIRIDTSCVCALSRKIGRT

An example of a glial-derived neurotropic factor (GDNF) is provided by Genbank NM_(—)000514 and shown below:

(SEQ ID NO: 47) MKLWDVVAVCLVLLHTASAFPLPAGKRPPEAPAEDRSLGRRRAPF ALSSDSNMPEDYPDQFDDVMDFIQATIKRLKRSPDKQMAVLPRRE RNRQAAAANPENSRGKGRRGQRGKNRGCVLTAIHLNVTDLGLGYE TKEELIFRYCSGSCDAAETTYDKILKNLSRNRRLVSDKVGQACCR PIAFDDDLSFLDDNLVYHILRKHSAKRCGCI

Thus, a recombinant nucleic acid molecule of the invention can be used to promote the growth (regeneration) of axons that have been injured, as well as modify the activity or function of the axons in a mammalian neuron as further described herein in the methods of the invention.

The selected polypeptide encoded by a recombinant nucleic acid molecule of the invention can also be any polypeptide the expression of which can be easily detected. For example, the selected polypeptide can be a green fluorescent protein (GFP) or Cherry. These polypeptides are useful as reporters for gene expression in neuronal axons.

An example of a nucleic acid sequence of the invention is as follows:

(SEQ ID NO: 48) gcccctctccctcccccccccctaacgttactggccgaagccgct tggaataaggccggtgtgcgtttgtctatatgttattttccacca tattgccgtcttttggcaatgtgagggcccggaaacctggccctg tcttcttgacgagcattcctaggggtctttcccctctcgccaaag gaatgcaaggtctgttgaatgtcgtgaaggaagcagttcctctgg aagcttcttgaagacaaacaacgtctgtagcgaccctttgcaggc agcggaaccccccacctggcgacaggtgcctctgcggccaaaagc cacgtgtataagatacacctgcaaaggcggcacaaccccagtgcc acgttgtgagttggatagttgtggaaagagtcaaatggctctcct caagcgtattcaacaaggggctgaaggatgcccagaaggtacccc attgtatgggatctgatctggggcctcggtgcacatgctttacat gtgtttagtcgaggttaaaaaaacgtctaggccccccgaaccacg gggacgtggttttcctttgaaaaacacgatgataagcttgccaca acgcgtgccgccaccATG GGTGCAGAAGAACAGAAGCTGATCTCA GAGGAGGACCTGGGTGTGAGCAAGGGCGAGGAGGATAACATGGCC ATCATCAAGGAGTTCATGCGCTTCAAGGTGCACATGGAGGGCTCC GTGAACGGCCACGAGTTCGAGATCGAGGGCGAGGGCGAGGGCCGC CCCTACGAGGGCACCCAGACCGCCAAGCTGAAGGTGACCAAGGGT GGCCCCCTGCCCTTCGCCTGGGACATCCTGTCCCCTCAGTTCATG TACGGCTCCAAGGCCTACGTGAAGCACCCCGCCGACATCCCCGAC TACTTGAAGCTGTCCTTCCCCGAGGGCTTCAAGTGGGAGCGCGTG ATGAACTTGGAGGACGGCGGCGTGGTGACCGTGACCCAGGACTCC TCCCTGCAGGACGGCGAGTTCATCTACAAGGTGAAGCTGCGCGGC ACCAACTTCCCCTCCGACGGCCCCGTAATGCAGAAGAAGACCATG GGCTGGGAGGCCTCCTCCGAGCGGATGTACCCCGAGGACGGCGCC CTGAAGGGCGAGATCAAGCAGAGGCTGAAGCTGAAGGACGGCGGC CACTACGACGCTGAGGTCAAGACCACCTACAAGGCCAAGAAGCCC GTGCAGCTGCCCGGCGCCTACAACGTCAACATCAAGTTGGACATC ACCTCCCACAACGAGGACTACACCATCGTGGAACAGTACGAACGC GCCGAGGGCCGCCACTCCACCGGCGGCATGGACGAGCTGTACAAG AGC In the above sequence, the IRES sequence is shown in small letters and italicized. The polypeptide coding sequence is shown in capital letters with the ATG start codon bolded. There is an eleven-nucleotide spacer between the IRES sequence and the ATG start codon. The underlined sequence encodes for the myc tag and the remaining sequence codes for Cherry. Other nucleic acids of the invention can have the same IRES sequence shown above covalently-linked, i.e. by a phosphodiester bond, to a coding sequence for RhoA or sAC for example. Non-limiting examples of polypeptide-coding sequences that can be ligated to the above sequence, to the above IRES sequence or to any IRES sequence, to form a nucleic acid of the invention are shown below with their 3′ untranslated regions. Nucleic acid encoding a C3-ADP-ribosyltransferase (Genbank M74038):

(SEQ ID NO: 49) 435                ATGAAA GGGATAAGAA AGTCAATTTT ATGTTTAGTT TTATCAGCAG 481 GGGTAATAGC TCCGGTAACA ACGAGTATAG TTCAAAGTCC TCAAAAATGT TATGCTTGTA 541 CTGTTGATAA AGGTTCATAT GCAGATACTT TCACAGAATT TACCAATGTT GAGGAAGCCA 601 AAAAATGGGG AAATGCTCAA TATAAAAAAT ATGGCCTAAG CAAACCTGAA CAAGAAGCTA 661 TAAAATTTTA TACAAGAGAT GCAAGTAAGA TCAATGGACC ATTAAGAGCA AATCAAGGGA 721 ATGAAAATGG ATTACCTGCT GATATATTAC AAAAAGTTAAA TTAATTGAT CAATCTTTTA 781 GTAAGATGAA GATGCCTCAA AATATTATTC TTTTTAGAGG TGATGACCCT GCTTATTTAG 841 GTCCAGAATT TCAAGATAAA ATTCTTAATA AAGATGGAAC AATTAATAAA ACTGTTTTTG 901 AACAAGTTAA AGCGAAATTT TTAAAAAAGG ATAGAACAGA ATATGGATAT ATTAGTACTT 961 CATTAATGAG TGCGCAATTT GGAGGAAGAC CAATTGTTAC TAAATTTAAA GTAACTAATG 1021 GATCAAAAGG AGGGTATATA GACCCTATTA GCTATTTCCC AGGACAACTT GAAGTGTTGC 1081 TTCCTAGAAA TAATAGTTAT TATATAAGTG ATATGCAAAT ATCTCCTAAT AATAGACAAA 1141 TTATGATTAC AGCAATGATA TTTAAATAGt ttataaaaat aaataaaata tagttatgct 1201 aaataaaaga tttagcatct tgaagtaaga aaaattatag gaacacataa caacaaaaat 1261 aactactttt aattaagtag ttcagattgt tcaaaaagcc tccatgtaat tggaggcttt 1321 tactttcgtc aaatatcttt tatgcgatag catttaaaa agttgctagtt ttgtgtaatg 1381 atttggtata aatttcaatt aaatcatacg aaaaatagtg cgatagcacc atggctatct 1441 ttttcatatt ctgaactgct gctgtaatga agcattgctc ggaaacattt ttaattcctc 1501 gcatgcgaca atagcgcagc ccatgtaatt cttttgaatc agcaaactac gctcaatttt 1561 ttctttacgt tttttataaa tacttttacc tttttcagtt ttagtaaatg caaaaatttg 1621 atccttataa tcttcccaaa catgacgacg tatagctttg ttaattgatt tatcagatgt 1681 taagcaatta tttttatatt tgcatgaagc acattcatcc gcattactaa catattcttt 1741 atatccgctt cttgtagtgg ttttgtattt taaaaagaag ttattcatac atacatatcc 1801 atctaattct ttaatatatt gaaatctata tttagtatac ttttctttaa catgaggtcc 1861 taaacggaaa ccaaaaacac cttgataatt tttttctgaa acttgcttac aaataggatt 1921 tgtagaataa ccagcatcag ctactaaata ctttgtatta aaattaaact tttttatttg 1981 cgtctctatt cttttaacat aaggatctac atcattaata ttacctggag ttacatgaac 2041 atcagttata atattatatt ttccgtc A nucleic acid sequence encoding human N19-RhoA 9 Genbank (NM_(—)001664):

(SEQ ID NO: 50) 277                                        ATGG CTGCCATCCG GAAGAAACTG 301 GTGATTGTTG GTGATGGAGC CTGTGGAAAG ACATGCTTGC TCATAGTCTT CAGCAAGGAC 361 CAGTTCCCAG AGGTGTATGT GCCCACAGTG TTTGAGAACT ATGTGGCAGA TATCGAGGTG 421 GATGGAAAGC AGGTAGAGTT GGCTTTGTGG GACACAGCTG GGCAGGAAGA TTATGATCGC 481 CTGAGGCCCC TCTCCTACCC AGATACCGAT GTTATACTGA TGTGTTTTTC CATCGACAGC 541 CCTGATAGTT TAGAAAACAT CCCAGAAAAG TGGACCCCAG AAGTCAAGCA TTTCTGTCCC 601 AACGTGCCCA TCATCCTGGT TGGGAATAAG AAGGATCTTC GGAATGATGA GCACACAAGG 661 CGGGAGCTAG CCAAGATGAA GCAGGAGCCG GTGAAACCTG AAGAAGGCAG AGATATGGCA 721 AACAGGATTG GCGCTTTTGG GTACATGGAG TGTTCAGCAA AGACCAAAGA TGGAGTGAGA 781 GAGGTTTTTG AAATGGCTAC GAGAGCTGCT CTGCAAGCTA GACGTGGGAA GAAAAAATCT 841 GGGTGCCTTG TCTTGTGAAA CCTTGCTGCA AGCACAGCCC TTATGCGGTT AATTTTGAAG 901 TGCTGTTTAT TAATCTTAGT GTATGATTAC TGGCCTTTTT CATTTATCTA TAATTTACCT 961 AAGATTACAA ATCAGAAGTC ATCTTGCTAC CAGTATTTAG AAGCCAACTA TGATTATTAA 1021 CGATGTCCAA CCCGTCTGGC CCACCAGGGT CCTTTTGACA CTGCTCTAAC AGCCCTCCTC 1081 TGCACTCCCA CCTGACACAC CAGGCGCTAA TTCAAGGAAT TTCTTAACTT CTTGCTTCTT 1141 TCTAGAAAGA GAAACAGTTG GTAACTTTTG TGAATTAGGC TGTAACTACT TTATAACTAA 1201 CATGTCCTGC CTATTATCTG TCAGCTGCAA GGTACTCTGG TGAGTCACCA CTTCAGGGCT 1261 TTACTCCGTA ACAGATTTTG TTGGCATAGC TCTGGGGTGG GCAGTTTTTT GAAAATGGGC 1321 TCAACCAGAA AAGCCCAAGT TCATGCAGCT GTGGCAGAGT TACAGTTCTG TGGTTTCATG 1381 TTAGTTACCT TATAGTTACT GTGTAATTAG TGCCACTTAA TGTATGTTAC CAAAAATAAA 1441 TATATCTACC CCAGACTAGA TGTAGTATTT TTTGTATAAT TGGATTTCCT AATACTGTCA 1501 TCCTCAAAGA AAGTGTATTG GTTTTTTAAA AAAGAAAGTG TATTTGGAAA TAAAGTCAGA 1561 TGGAAAATTC ATTTTTTAAA TTCCCGTTTT GTCACTTTTT CTGATAAAAG ATGGCCATAT 1621 TACCCCTTTT CGGCCCCATG TATCTCAGTA CCCCATGGAG CTGGGCTAAG TAAATAGGAA 1681 TTGGTTTCAC GCCTGAGGCA ATTAGACACT TTGGAAGATG GCATAACCTG TCTCACCTGG 1741 ACTTAAGCAT CTGGCTCTAA TTCACAGTGC TCTTTTCTCC TCACTGTATC CAGGTTCCCT 1801 CCCAGAGGAG CCACCAGTTC TCATGGGTGG CACTCAGTCT CTCTTCTCTC CAGCTGACTA 1861 AACTTTTTTT CTGTACCAGT TAATTTTTCC AACTACTAAT AGAATAAAGG CAGTTTTCTA 1921 AAAAAA

Nucleic acid encoding a dominant-negative RhoA kinase (ROCK) (Genbank NM_(—)005406)

(SEQ ID NO: 51) 942                                              ATGTCGACT GGGGACAGTT 961 TTGAGACTCG ATTTGAAAAA ATGGACAACC TGCTGCGGGA TCCCAAATCG GAAGTGAATT 1021 CGGATTGTTT GCTGGATGGA TTGGATGCTT TGGTATATGA TTTGGATTTT CCTGCCTTAA 1081 GAAAAAACAA AAATATTGAC AACTTTTTAA GCAGATATAA AGACACAATA AATAAAATCA 1141 GAGATTTACG AATGAAAGCT GAAGATTATG AAGTAGTGAA GGTGATTGGT AGAGGTGCAT 1201 TTGGAGAAGT TCAATTGGTA AGGCATAAAT CCACCAGGAA GGTATATGCT ATGAAGCTTC 1261 TCAGCAAATT TGAAATGATA AAGAGATCTG ATTCTGCTTT TTTCTGGGAA GAAAGGGACA 1321 TCATGGCTTT TGCCAACAGT CCTTGGGTTG TTCAGCTTTT TTATGCATTC CAAGATGATC 1381 GTTATCTCTA CATGGTGATG GAATACATGC CTGGTGGAGA TCTTGTAAAC TTAATGAGCA 1441 ACTATGATGT GCCTGAAAAA TGGGCACGAT TCTATACTGC AGAAGTAGTT CTTGCATTGG 1501 ATGCAATCCA TTCCATGGGT TTTATTCACA GAGATGTGAA GCCTGATAAC ATGCTGCTGG 1561 ATAAATCTGG ACATTTGAAG TTAGCAGATT TTGGTACTTG TATGAAGATG AATAAGGAAG 1621 GCATGGTACG ATGTGATACA GCGGTTGGAA CACCTGATTA TATTTCCCCT GAAGTATTAA 1681 AATCCCAAGG TGGTGATGGT TATTATGGAA GAGAATGTGA CTGGTGGTCG GTTGGGGTAT 1741 TTTTATACGA AATGCTTGTA GGTGATACAC CTTTTTATGC AGATTCTTTG GTTGGAACTT 1801 ACAGTAAAAT TATGAACCAT AAAAATTCAC TTACCTTTCC TGATGATAAT GACATATCAA 1861 AAGAAGCAAA AAACCTTATT TGTGCCTTCC TTACTGACAG GGAAGTGAGG TTAGGGCGAA 1921 ATGGTGTAGA AGAAATCAAA CGACATCTCT TCTTCAAAAA TGACCAGTGG GCTTGGGAAA 1981 CGCTCCGAGA CACTGTAGCA CCAGTTGTAC CCGATTTAAG TAGTGACATT GATACTAGTA 2041 ATTTTGATGA CTTGGAAGAA GATAAAGGAG AGGAAGAAAC ATTCCCTATT CCTAAAGCTT 2101 TCGTTGGCAA TCAACTACCT TTTGTAGGAT TTACATATTA TAGCAATCGT AGATACTTAT 2161 CTTCAGCAAA TCCTAATGAT AACAGAACTA GCTCCAATGC AGATAAAAGC TTGCAGGAAA 2221 GTTTGCAAAA AACAATCTAT AAGCTGGAAG AACAGCTGCA TAATGAAATG CAGTTAAAAG 2281 ATGAAATGGA GCAGAAGTGC AGAACCTCAA ACATAAAACT AGACAAGATA ATGAAAGAAT 2341 TGGATGAAGA GGGAAATCAA AGAAGAAATC TAGAATCTAC AGTGTCTCAG ATTGAGAAGG 2401 AGAAAATGTT GCTACAGCAT AGAATTAATG AGTACCAAAG AAAAGCTGAA CAGGAAAATG 2461 AGAAGAGAAG AAATGTAGAA AATGAAGTTT CTACATTAAA GGATCAGTTG GAAGACTTAA 2521 AGAAAGTCAG TCAGAATTCA CAGCTTGCTA ATGAGAAGCT GTCCCAGTTA CAAAAGCAGC 2581 TAGAAGAAGC CAATGACTTA CTTAGGACAG AATCGGACAC AGCTGTAAGA TTGAGGAAGA 2641 GTCACACAGA GATGAGCAAG TCAATTAGTC AGTTAGAGTC CCTGAACAGA GAGTTGCAAG 2701 AGAGAAATCG AATTTTAGAG AATTCTAAGT CACAAACAGA CAAAGATTAT TACCAGCTGC 2761 AAGCTATATT AGAAGCTGAA CGAAGAGACA GAGGTCATGA TTCTGAGATG ATTGGAGACC 2821 TTCAAGCTCG AATTACATCT TTACAAGAGG AGGTGAAGCA TCTCAAACAT AATCTCGAAA 2881 AAGTGGAAGG AGAAAGAAAA GAGGCTCAAG ACATGCTTAA TCACTCAGAA AAGGAAAAGA 2941 ATAATTTAGA GATAGATTTA AACTACAAAC TTAAATCATT ACAACAACGG TTAGAACAAG 3001 AGGTAAATGA ACACAAAGTA ACCAAAGCTC GTTTAACTGA CAAACATCAA TCTATTGAAG 3061 AGGCAAAGTC TGTGGCAATG TGTGAGATGG AAAAAAAGCT GAAAGAAGAA AGAGAAGCTC 3121 GAGAGAAGGC TGAAAATCGG GTTGTTCAGA TTGAGAAACA GTGTTCCATG CTAGACGTTG 3181 ATCTGAAGCA ATCTCAGCAG AAACTAGAAC ATTTGACTGG AAATAAAGAA AGGATGGAGG 3241 ATGAAGTTAA GAATCTAACC CTGCAACTGG AGCAGGAATC AAATAAGCGG CTGTTGTTAC 3301 AAAATGAATT GAAGACTCAA GCATTTGAGG CAGACAATTT AAAAGGTTTA GAAAAGCAGA 3361 TGAAACAGGA AATAAATACT TTATTGGAAG CAAAGAGATT ATTAGAATTT GAGTTAGCTC 3421 AGCTTACGAA ACAGTATAGA GGAAATGAAG GACAGATGCG GGAGCTACAA GATCAGCTTG 3481 AAGCTGAGCA ATATTTCTCG ACACTTTATA AAACCCAGGT AAAGGAACTT AAAGAAGAAA 3541 TTGAAGAAAA AAACAGAGAA AATTTAAAGA AAATACAGGA ACTACAAAAT GAAAAAGAAA 3601 CTCTTGCTAC TCAGTTGGAT CTAGCAGAAA CAAAAGCTGA GTCTGAGCAG TTGGCGCGAG 3661 GCCTTCTGGA AGAACAGTAT TTTGAATTGA CGCAAGAAAG CAAGAAAGCT GCTTCAAGAA 3721 ATAGACAAGA GATTACAGAT AAAGATCACA CTGTTAGTCG GCTTGAAGAA GCAAACAGCA 3781 TGCTAACCAA AGATATTGAA ATATTAAGAA GAGAGAATGA AGAGCTAACA GAGAAAATGA 3841 AGAAGGCAGA GGAAGAATAT AAACTGGAGA AGGAGGAGGA GATCAGTAAT CTTAAGGCTG 3901 CCTTTGAAAA GAATATCAAC ACTGAACGAA CCCTTAAAAC ACAGGCTGTT AACAAATTGG 3961 CAGAAATAAT GAATCGAAAA GATTTTAAAA TTGATAGAAA GAAAGCTAAT ACACAAGATT 4021 TGAGAAAGAA AGAAAAGGAA AATCGAAAGC TGCAACTGGA ACTCAACCAA GAAAGAGAGA 4081 AATTCAACCA GATGGTAGTG AAACATCAGA AGGAACTGAA TGACATGCAA GCGCAATTGG 4141 TAGAAGAATG TGCACATAGG AATGAGCTTC AGATGCAGTT GGCCAGCAAA GAGAGTGATA 4201 TTGAGCAATT GCGTGCTAAA CTTTTGGACC TCTCGGATTC TACAAGTGTT GCTAGTTTTC 4261 CTAGTGCTGA TGAAACTGAT GGTAACCTCC CAGAGTCAAG AATTGAAGGT TGGCTTTCAG 4321 TACCAAATAG AGGAAATATC AAACGATATG GCTGGAAGAA ACAGTATGTT GTGGTAAGCA 4381 GCAAAAAAAT TTTGTTCTAT AATGACGAAC AAGATAAGGA GCAATCCAAT CCATCTATGG 4441 TATTGGACAT AGATAAACTG TTTCACGTTA GACCTGTAAC CCAAGGAGAT GTGTATAGAG 4501 CTGAAACTGA AGAAATTCCT AAAATATTCC AGATACTATA TGCAAATGAA GGTGAATGTA 4561 GAAAAGATGT AGAGATGGAA CCAGTACAAC AAGCTGAAAA AACTAATTTC CAAAATCACA 4621 AAGGCCATGA GTTTATTCCT ACACTCTACC ACTTTCCTGC CAATTGTGAT GCCTGTGCCA 4681 AACCTCTCTG GCATGTTTTT AAGCCACCCC CTGCCCTAGA GTGTCGAAGA TGCCATGTTA 4741 AGTGCCACAG AGATCACTTA GATAAGAAAG AGGACTTAAT TTGTCCATGT AAAGTAAGTT 4801 ATGATGTAAC ATCAGCAAGA GATATGCTGC TGTTAGCATG TTCTCAGGAT GAACAAAAAA 4861 AATGGGTAAC TCATTTAGTA AAGAAAATCC CTAAGAATCC ACCATCTGGT TTTGTTCGTG 4921 CTTCCCCTCG AACGCTTTCT ACAAGATCCA CTGCAAATCA GTCTTTCCGG AAAGTGGTCA 4981 AAAATACATC TGGAAAAACT AGTTAAccat gtgactgagt gccctgtgga atcgtgtggg 5041 atgctacctg ataaaccagg cttctttaac catgcagagc agacaggctg tttctttgac 5101 acaaatatca caggcttcag ggttaagatt gctgtttttc tgtccttgct ttggcacaac 5161 acactgaggg ttttttttat tgcgggtttg cctacaggta gattagatta attattacta 5221 tgtaatgcaa gtacagttgg gggaaagctt aggtagatat atttttttta aaaggtgctg 5281 cctttttgga tttataagaa aatgcctgtc agtcgtgata gaacagagtt ttcctcatat 5341 gagtaagagg aagggacttt cactttcaag tggaacagcc atcactatca agatcagctc 5401 atggaaggag taaagaaaat atctcaaaat gagacaaact gaagttttgt ttttttttta 5461 atgacttaag tttttgtgct cttgcaagac tatacaaaac tattttaaga aagcagtgat 5521 atcacttgaa cttcagtgcc ctcactgtag aatttaaaag ccttactgtt gattgcccat 5581 gttggacttg atggagaaat taaatatctt tcattatgct ttacaaaata ctgtatatgt 5641 ttcagcaagt ttggggaatg ggagaggaca aaaaaaagtt acatttaatc tatgcatttt 5701 tgccaagcca tattgagtta ttttactact agagacatta ggaaactaac tgtacaaaag 5761 aaccaagttt aaaagcattt tgtggggtac atcatttcta taattgtata atgtatttct 5821 ttgtggtttt aaatgataaa gacattaagt taacaaacat ataagaaatg tatgcactgt 5881 ttgaaatgta aattattctt agaacacttt caatgggggt tgcattgtcc ttttagtgcc 5941 ttaatttgag ataattattt tactgccatg agtaagtata gaaatttcaa aaaatgtatt 6001 ttcaaaaaat tatgtgtgtc agtgagtttt tcattgataa ttggtttaat ttaaaatatt 6061 tagaggtttg ttggactttc ataaattgag tacaatcttt gcatcaaact acctgctaca 6121 ataatgactt tataaaactg caaaaaatgt agaaggttgc accaacataa aaaggaaata 6181 tggcaataca tccatgatgt tttccagtta acataggaat taccagataa atactgttaa 6241 actcttgtcc agtaacaaga gttgattcat atggacagta tgatttattg tttatttttt 6301 taaccaaata cctcctcagt aatttataat ggctttgcag taatgtgtat cagataagaa 6361 gcactggaaa accgatcgtc tctaggatga tatgcatgtt tcaagtggta ttgaaagccg 6421 cactgatgga tatgtaataa taaacatatc tgttattaat atactaatga ctctgtgctc 6481 atttaatgag aaataaaagt aatttatgga tgggtatctt taatttttac tgcaatgtgt 6541 tttctcatgg ctgaaatgaa tggaaaacat acttcaaatt agtctctgat tgtatataaa 6601 tgtttgtgaa attccatggt tagattaaag tgtattttta aaagataaaa

Nucleic acid encoding a soluble adenylyl cyclase sequence (Genbank NM_(—)018417)

(SEQ ID NO: 52) 299                                                                AT 301 GAACACTCCA AAAGAAGAAT TCCAGGACTG GCCCATAGTC AGAATAGCAG CTCATTTACC 361 AGACCTCATT GTCTATGGAC ATTTCTCCCC AGAGCGACCC TTTATGGATT ATTTTGACGG 421 AGTCCTGATG TTTGTTGATA TTTCAGGTTT TACTGCAATG ACTGAGAAGT TCAGCAGTGC 481 CATGTACATG GACAGAGGGG CTGAGCAGTT GGTGGAGATC CTCAACTACC ACATAAGTGC 541 AATAGTGGAG AAAGTGTTGA TTTTTGGAGG AGACATCCTG AAATTTGCAG GTGATGCACT 601 GCTAGCCCTG TGGAGGGTGG AGCGAAAGCA GCTGAAAAAC ATTATCACAG TGGTAATTAA 661 ATGTAGCCTG GAGATCCATG GATTGTTTGA GACCCAGGAG TGGGAAGAAG GCCTAGACAT 721 CCGAGTCAAG ATAGGACTGG CTGCTGGCCA CATCAGCATG TTGGTCTTTG GAGATGAAAC 781 ACACAGCCAC TTTCTGGTGA TTGGTCAGGC AGTGGACGAT GTGCGCCTTG CCCAGAACAT 841 GGCTCAGATG AATGATGTTA TTCTGTCACC AAACTGCTGG CAGCTCTGTG ACCGGAGCAT 901 GATTGAAATT GAGAGTGTTC CAGATCAGAG AGCAGTTAAG GTTAACTTCT TAAAACCACC 961 CCCCAATTTT AATTTTGATG AATTTTTCAC AAAGTGTACG ACCTTCATGC ATTATTATCC 1021 TTCTGGTGAG CACAAAAACC TCCTGAGGCT TGCATGCACG CTGAAGCCTG ATCCTGAACT 1081 GGAGATGTCC CTACAAAAGT ATGTGATGGA AAGCATTTTG AAGCAGATTG ATAACAAACA 1141 GCTTCAGGGC TATTTATCTG AGCTTCGCCC AGTGACGATT GTGTTTGTGA ACCTGATGTT 1201 TGAAGACCAA GACAAAGCAG AAGAGATAGG CCCAGCCATC CAGGATGCCT ATATGCACAT 1261 CACTTCTGTC CTGAAGATCT TCCAAGGCCA AATCAATAAA GTCTTCATGT TTGACAAGGG 1321 CTGCTCTTTC CTCTGTGTCT TTGGCTTCCC TGGGGAAAAG GTACCTGACG AGCTCACTCA 1381 TGCTCTGGAA TGTGCTATGG ATATATTTGA CTTCTGCTCT CAAGTCCACA AAATCCAAAC 1441 TGTATCCATC GGTGTTGCCA GTGGGATTGT CTTCTGTGGG ATCGTTGGAC ACACTGTGAG 1501 ACACGAGTAC ACAGTCATTG GTCAAAAAGT CAACTTAGCT GCCAGGATGA TGATGTACTA 1561 CCCAGGAATT GTGACCTGCG ACTCTGTCAC CTACAATGGG AGCAACCTAC CAGCGTACTT 1621 TTTTAAAGAG CTTCCAAAGA AAGTTATGAA AGGTGTTGCA GATTCTGGAC CATTGTATCA 1681 GTATTGGGGC CGTACTGAGA AAGTCATGTT TGGTATGGCG TGCCTCATCT GCAACAGAAA 1741 GGAGGATTAC CCTTTGCTGG GACGTAATAA AGAGATCAAC TACTTCATGT ATACTATGAA 1801 GAAATTTTTG ATATCTAACA GCAGCCAAGT CTTAATGTAT GAGGGATTAC CAGGATATGG 1861 AAAAAGCCAG ATACTTATGA AAATTGAGTA CCTGGCCCAA GGTAAGAATC ACAGGATTAT 1921 TGCCATTTCA TTGAATAAGA TCAGCTTCCA TCAAACTTTC TATACCATCC AGATGTTCAT 1981 GGCCAATGTC CTAGGCCTAG ACACTTGTAA ACATTATAAA GAACGACAGA CCAACCTTCG 2041 AAATAAAGTC ATGACACTGT TGGATGAAAA GTTCTACTGT CTTCTTAATG ACATTTTCCA 2101 TGTTCAGTTC CCTATTTCTC GGGAGATTTC CAGGATGAGC ACCTTGAAAA AGCAAAAACA 2161 ATTGGAAATA TTGTTTATGA AGATCTTGAA GCTGATAGTG AAAGAGGAAA GGATTATTTT 2221 TATCATTGAT GAGGCCCAGT TTGTGGATTC GACCTCCTGG AGATTTATGG AGAAGCTTAT 2281 CCGGACTCTT CCTATCTTCA TCATTATGTC CCTGTGTCCC TTCGTTAACA TTCCCTGTGC 2341 AGCTGCCAGG GCCGTAATAA AGAACAGGAA CACCACCTAC ATTGTCATTG GTGCAGTACA 2401 GCCTAACGAC ATCTCCAACA AGATCTGTCT TGACCTCAAT GTGAGCTGCA TCTCCAAAGA 2461 ACTGGACTCG TACCTGGGGG AGGGAAGCTG TGGGATTCCA TTTTACTGTG AAGAATTGCT 2521 TAAAAACCTG GAACATCATG AGGTACTCGT TTTCCAACAA ACGGAGTCTG AGGAAAAGAC 2581 AAATAGGACC TGGAATAACC TGTTCAAGTA TTCCATTAAG CTAACAGAGA AGTTAAACAT 2641 GGTTACTCTC CATAGTGATA AGGAAAGTGA AGAAGTCTGT CACCTCACAA GTGGTGTCAG 2701 ACTGAAAAAC CTGTCACCTC CAACGTCATT AAAAGAAATC TCTCTGATCC AGCTGGATAG 2761 CATGAGACTT TCCCACCAAA TGCTGGTGAG ATGTGCTGCC ATCATTGGCC TGACCTTCAC 2821 CACTGAGTTG TTGTTTGAGA TTCTCCCCTG TTGGAATATG AAGATGATGA TCAAGACCCT 2881 GGCAACCCTA GTGGAATCTA ACATTTTTTA TTGTTTCCGG AATGGCAAGG AGCTTCAAAA 2941 GGCCCTGAAA CAGAATGATC CCTCATTTGA GGTGCACTAT CGTTCCTTGT CTCTGAAGCC 3001 CAGTGAAGGG ATGGATCACG GTGAAGAGGA ACAGCTTCGT GAACTGGAGA ATGAGGTGAT 3061 CGAGTGCCAC AGGATTCGAT TCTGTAACCC TATGATGCAG AAAACAGCCT ACGAGCTGTG 3121 GCTCAAGGAC CAGAGAAAAG CCATGCACTT GAAATGTGCC CGCTTTTTAG AAGAAGATGC 3181 CCACAGATGT GACCACTGCC GAGGCAGGGA CTTCATTCCC TATCATCACT TCACAGTGAA 3241 TATTCGGCTC AACGCTTTAG ACATGGATGC CATTAAAAAG ATGGCTATGT CTCATGGATT 3301 TAAAACTGAA GAAAAGCTTA TCTTGTCCAA CTCAGAGATT CCTGAGACAT CTGCATTTTT 3361 TCCTGAAAAT CGCAGTCCTG AAGAAATAAG AGAAAAGATC TTGAATTTCT TTGACCACGT 3421 TTTAACAAAA ATGAAGACAT CTGACGAAGA CATTATCCCT CTGGAATCTT GCCAGTGTGA 3481 AGAAATCCTA GAGATTGTCA TCTTGCCTCT GGCCCACCAT TTTCTGGCTT TGGGAGAAAA 3541 TGACAAAGCC TTATATTACT TCTTAGAAAT TGCATCTGCT TATCTCATCT TTTGTGATAA 3601 CTACATGGCA TACATGTATT TGAATGAAGG ACAGAAGTTG CTAAAAACTC TCAAGAAGGA 3661 CAAATCTTGG AGCCAGACAT TTGAGTCTGC CACCTTTTAC AGCCTCAAAG GTGAGGTCTG 3721 TTTCAATATG GGCCAGATAG TGCTTGCCAA GAAAATGCTG AGGAAGGCAC TGAAGCTCCT 3781 CAACCGAATC TTTCCTTACA ACTTAATCTC CTTGTTTCTC CATATCCATG TCGAGAAAAA 3841 CAGACACTTT CATTATGTGA ATCGGCAGGC CCAAGAGAGC CCACCTCCAG GGAAGAAGAG 3901 GCTGGCACAA CTTTACCGGC AAACTGTCTG CCTTTCCTTG CTGTGGCGCA TCTATAGCTA 3961 CAGTTATCTT TTTCACTGCA AGTATTATGC CCACCTGGCA GTTATGATGC AAATGAATAC 4021 TGCACTGGAA ACTCAAAATT GTTTCCAGAT CATTAAGGCT TACCTAGACT ATTCGCTATA 4081 CCACCACCTG GCTGGCTACA AAGGTGTGTG GTTCAAATAT GAAGTCATGG CCATGGAGCA 4141 CATCTTCAAC CTCCCCCTGA AAGGCGAGGG CATTGAAATC GTGGCATACG TGGCTGAGAC 4201 ACTGGTCTTC AACAAGCTCA TAATGGGACA CCTGGATTTG GCCATTGAGT TAGGCTCCCG 4261 AGCCCTTCAG ATGTGGGCAC TGCTCCAGAA TCCCAACCGA CATTATCAGT CCCTCTGCAG 4321 ACTTAGCAGA TGTCTCCTTC TGAACAGCAG ATACCCGCAA TTGATCCAGG TGCTGGGGCG 4381 GCTGTGGGAG CTTTCTGTAA CACAGGAACA CATCTTCAGC AAGGCATTTT TCTATTTTGT 4441 CTGCTTGGAC ATCCTGCTTT ATTCTGGTTT TGTTTATAGA ACATTTGAAG AATGTTTGGA 4501 ATTCATACAC CAATACGAAA ACAACAGAAT CCTCAAGTTC CACAGTGGAC TCCTCCTGGG 4561 ACTTTATTCC TCTGTAGCTA TCTGGTATGC CAGACTTCAG GAATGGGACA ACTTTTACAA 4621 ATTTTCCAAT AGAGCTAAAA ATCTTTTGCC AAGAAGAACC ATGACACTTA CTTACTATGA 4681 CGGAATATCT AGGTACATGG AGGGGCAAGT TCTTCACCTT CAAAAACAAA TCAAAGAACA 4741 GTCAGAGAAT GCCCAAGCCA GTGGGGAGGA GCTACTCAAG AACTTGGAGA ATCTGGTGGC 4801 TCAAAATACC ACTGGCCCTG TCTTTTGCCC AAGGCTCTAC CACCTGATGG CTTACGTCTG 4861 TATATTAATG GGAGATGGGC AGAAATGTGG CCTCTTCCTG AACACAGCCT TGCGGCTCTC 4921 TGAAACACAG GGGAATATAC TGGAGAAATG CTGGCTGAAC ATGAACAAAG AATCATGGTA 4981 CTCAACCTCT GAGTTAAAAG AAGACCAATG GCTTCAGACG ATCTTGAGTC TCCCATCATG 5041 GGAAAAAATT GTAGCAGGCA GGGTAAACAT TCAGGATCTT CAAAAAAACA AATTCCTGAT 5101 GAGAGCTAAT ACCGTGGACA ATCATTTCTA Acatgtcaaa gaaaaaagat tttaataagc 5161 actatgtcct tgtgattatc tattattgac ctttctccgt ggctggcc

Nucleic acid encoding a glutamic acid decarboxylase (GAD) (Genbank NM_(—)000817)

(SEQ ID NO: 53) 423   ATGGCGTC TTCGACCCCA TCTTCGTCCG CAACCTCCTC GAACGCGGGA GCGGACCCCA 481 ATACCACTAA CCTGCGCCCC ACAACGTACG ATACCTGGTG CGGCGTGGCC CATGGATGCA 541 CCAGAAAACT GGGGCTCAAG ATCTGCGGCT TCTTGCAAAG GACCAACAGC CTGGAAGAGA 601 AGAGTCGCCT TGTGAGTGCC TTCAAGGAGA GGCAATCCTC CAAGAACCTG CTTTCCTGTG 661 AAAACAGCGA CCGGGATGCC CGCTTCCGGC GCACAGAGAC TGACTTCTCT AATCTGTTTG 721 CTAGAGATCT GCTTCCGGCT AAGAACGGTG AGGAGCAAAC CGTGCAATTC CTCCTGGAAG 781 TGGTGGACAT ACTCCTCAAC TATGTCCGCA AGACATTTGA TCGCTCCACC AAGGTGCTGG 841 ACTTTCATCA CCCACACCAG TTGCTGGAAG GCATGGAGGG CTTCAACTTG GAGCTCTCTG 901 ACCACCCCGA GTCCCTGGAG CAGATCCTGG TTGACTGCAG AGACACCTTG AAGTATGGGG 961 TTCGCACAGG TCATCCTCGA TTTTTCAACC AGCTCTCCAC TGGATTGGAT ATTATTGGCC 1021 TAGCTGGAGA ATGGCTGACA TCAACGGCCA ATACCAACAT GTTTACATAT GAAATTGCAC 1081 CAGTGTTTGT CCTCATGGAA CAAATAACAC TTAAGAAGAT GAGAGAGATA GTTGGATGGT 1141 CAAGTAAAGA TGGTGATGGG ATATTTTCTC CTGGGGGCGC CATATCCAAC ATGTACAGCA 1201 TCATGGCTGC TCGCTACAAG TACTTCCCGG AAGTTAAGAC AAAGGGCATG GCGGCTGTGC 1261 CTAAACTGGT CCTCTTCACC TCAGAACAGA GTCACTATTC CATAAAGAAA GCTGGGGCTG 1321 CACTTGGCTT TGGAACTGAC AATGTGATTT TGATAAAGTG CAATGAAAGG GGGAAAATAA 1381 TTCCAGCTGA TTTTGAGGCA AAAATTCTTG AAGCCAAACA GAAGGGATAT GTTCCCTTTT 1441 ATGTCAATGC AACTGCTGGC ACGACTGTTT ATGGAGCTTT TGATCCGATA CAAGAGATTG 1501 CAGATATATG TGAGAAATAT AACCTTTGGT TGCATGTCGA TGCTGCCTGG GGAGGTGGGC 1561 TGCTCATGTC CAGGAAGCAC CGCCATAAAC TCAACGGCAT AGAAAGGGCC AACTCAGTCA 1621 CCTGGAACCC TCACAAGATG ATGGGCGTGC TGTTGCAGTG CTCTGCCATT CTCGTCAAGG 1681 AAAAGGGTAT ACTCCAAGGA TGCAACCAGA TGTGTGCAGG ATACCTCTTC CAGCCAGACA 1741 AGCAGTATGA TGTCTCCTAC GACACCGGGG ACAAGGCAAT TCAGTGTGGC CGCCACGTGG 1801 ATATCTTCAA GTTCTGGCTG ATGTGGAAAG CAAAGGGCAC AGTGGGATTT GAAAACCAGA 1861 TCAACAAATG CCTGGAACTG GCTGAATACC TCTATGCCAA GATTAAAAAC AGAGAAGAAT 1921 TTGAGATGGT TTTCAATGGC GAGCCTGAGC ACACAAACGT CTGTTTTTGG TATATTCCAC 1981 AAAGCCTCAG GGGTGTGCCA GACAGCCCTC AACGACGGGA AAAGCTACAC AAGGTGGCTC 2041 CAAAAATCAA AGCCCTGATG ATGGAGTCAG GTACGACCAT GGTTGGCTAC CAGCCCCAAG 2101 GGGACAAGGC CAACTTCTTC CGGATGGTCA TCTCCAACCC AGCCGCTACC CAGTCTGACA 2161 TTGACTTCCT CATTGAGGAG ATAGAAAGAC TGGGCCAGGA TCTGTAAtca tccttcgcag 2221 aacatgagtt tatgggaatg ccttttccct ctggcactcc agaacaaacc tctatatgtt 2281 gctgaaacac acaggccatt tcattgaggg aaaacataat atcttgaaga atattgttaa 2341 aaccttactt aaagcttgtt tgttctagtt agcaggaaat agtgttcttt ttaaaaagtt 2401 gcacattagg aacagagtat atatgtacag ttatacatac ctctctctat atatacatgt 2461 atagtgagtg tggcttagta atagatcacg gcatgtttcc cgctccaaga gaattcactt 2521 taccttcagc agttaccgag gagctaaaca tgctgccaac cagcttgtcc aacaactcca 2581 ggaaaactgt ttttcaaaac gccatgtcct aggggccaag ggaaatgctg ttggtgagaa 2641 tcgacctcac tgtcagcgtt tctccacctg aagtgatgat ggatgagaaa aaacaccacc 2701 aaatgacaag tcacaccctc cccattagta tcctgttagg ggaaaatagt agcagagtca 2761 ttgttacagg tgtactatgg ctgtattttt agagattaat ttgtgtagat tgtgtaaatt 2821 cctgttgtct gaccttggtg gtgggagggg gagactatgt gtcatgattt caatgattgt 2881 ttaattgtag gtcaatgaaa tatttgctta tttatattca gagatgtacc atgttaaaga 2941 ggcgtcttgt attttcttcc catttgtaat gtatcttatt tatatatgaa gtaagttctg 3001 aaaactgttt atggtatttt cgtgcatttg tgagccaaag agaaaagatt aaaattagtg 3061 agatttgtat ttatattaga gtgcccttaa aataatgatt taagcatttt actgtctgta 3121 agagaattct aagattgtac ataaagtcat atatatggaa atcctgttac ttaaatagca 3181 tctgctcttc tcttacgctc tctgtctggc tgtacgtctg gtgttctcaa tgcttttcta 3241 gcaactgttg gataataact agatctcctg taattttgta gtagttgatg accaatctct 3301 gtgactcgct tagctgaaac ctaaggcaac atttccgaag accttctgaa gatctcagat 3361 aaagtgacca ggctcacaac tgtttttgaa gaagggaaat tcacactgtg cgttttagag 3421 tatgcaagaa gaatataaat aaataaaaat attctccatg gagaatttga acaaaaaaaa 3481 aaaaaaaa

Nucleic acid encoding human proenkephalin (Genbank NM_(—)006211):

(SEQ ID NO: 54) 82                        ATGGCGCGG TTCCTGACAC TTTGCACTTG GCTGCTGTTG 121 CTCGGCCCCG GGCTCCTGGC GACCGTGCGG GCCGAATGCA GCCAGGATTG CGCGACGTGC 181 AGCTACCGCC TAGTGCGCCC GGCCGACATC AACTTCCTGG CTTGCGTAAT GGAATGTGAA 241 GGTAAACTGC CTTCTCTGAA AATTTGGGAA ACCTGCAAGG AGCTCCTGCA GCTGTCCAAA 301 CCAGAGCTTC CTCAAGATGG CACCAGCACC CTCAGAGAAA ATAGCAAACC GGAAGAAAGC 361 CATTTGCTAG CCAAAAGGTA TGGGGGCTTC ATGAAAAGGT ATGGAGGCTT CATGAAGAAA 421 ATGGATGAGC TTTATCCCAT GGAGCCAGAA GAAGAGGCCA ATGGAAGTGA GATCCTCGCC 481 AAGCGGTATG GGGGCTTCAT GAAGAAGGAT GCAGAGGAGG ACGACTCGCT GGCCAATTCC 541 TCAGACCTGC TAAAAGAGCT TCTGGAAACA GGGGACAACC GAGAGCGTAG CCACCACCAG 601 GATGGCAGTG ATAATGAGGA AGAAGTGAGC AAGAGATATG GGGGCTTCAT GAGAGGCTTA 661 AAGAGAAGCC CCCAACTGGA AGATGAAGCC AAAGAGCTGC AGAAGCGATA TGGGGGCTTC 721 ATGAGAAGAG TAGGTCGCCC AGAGTGGTGG ATGGACTACC AGAAACGGTA TGGAGGTTTC 781 CTGAAGCGCT TTGCCGAGGC TCTGCCCTCC GACGAAGAAG GCGAAAGTTA CTCCAAAGAA 841 GTTCCTGAAA TGGAAAAAAG ATACGGAGGA TTTATGAGAT TTTAAtatct tttcccacta 901 gtggccccag gccccagcaa gcctccctcc atcctccagt gggaaactgt tgatggtgtt 961 ttattgtcat gtgttgcttg ccttgtatag ttgacttcat tgtctggata actatacaac 1021 ctgaaaactg tcatttcagg ttctgtgctc tttttggagt ctttaagctc agtattagtc 1081 tattgcagct atctcgtttt catgctaaaa tagtttttgt tatcttgtct cttatttttg 1141 acaaacatca ataaatgctt acttgtatat agagataata aacctattac cccaagtgca 1201 taaaaaaaaa aaaaaaaaaa a

Nucleic acid encoding a dominant-negative Vps24 sequence (Genbank NM_(—)016079):

(SEQ ID NO: 55) 130          A TGGGGCTGTT TGGAAAGACC CAGGAGAAGC CGCCCAAAGA ACTGGTCAAT 181 GAGTGGTCAT TGAAGATAAG AAAGGAAATG AGAGTTGTTG ACAGGCAAAT AAGGGATATC 241 CAAAGAGAAG AAGAAAAAGT GAAACGATCT GTGAAAGATG CTGCCAAGAA GGGCCAGAAG 301 GATGTCTGCA TAGTTCTGGC CAAGGAGATG ATCAGGTCAA GGAAGGCTGT GAGCAAGCTG 361 TATGCATCCA AAGCACACAT GAACTCAGTG CTCATGGGGA TGAAGAACCA GCTCGCGGTC 421 TTGCGAGTGG CTGGTTCCCT GCAGAAGAGC ACAGAAGTGA TGAAGGCCAT GCAAAGTCTT 481 GTGAAGATTC CAGAGATTCA GGCCACCATG AGGGAGTTGT CCAAAGAAAT GATGAAGGCT 541 GGGATCATAG AGGAGATGTT AGAGGACACT TTTGAAAGCA TGGACGATCA GGAAGAAATG 601 GAGGAAGAAG CAGAAATGGA AATTGACAGA ATTCTCTTTG AAATTACAGC AGGGGCCTTG 661 GGCAAAGCAC CCAGTAAAGT GACTGATGCC CTTCCAGAGC CAGAACCTCC AGGAGCGATG 721 GCTGCCTCAG AGGATGAGGA GGAGGAGGAA GAGGCTCTGG AGGCCATGCA GTCCCGGCTG 781 GCCACACTCC GCAGCTAGgg gctgcctacc ccgctgggtg tgcacacact cctctcaaga 841 gctgccattt tatgtgtctc ttgcactaca cctctgttgt gaggactacc attttggaga 901 aggttctgtt tgtctctttt cattctctgc ccaggttttg ggatcgcaaa gggattgttc 961 ttataaaagt ggcataaata aatgcatcat ttttaggagt atagacagat atatcttatt 1021 gtggggaggg gaaagaaatc catctgctca tgaagcactt ctgaaaatat aggtgattgc 1081 ctgaatgtcg aagactctac ttttgtctat aaaacactat ataaatgaat tttaataaat 1141 ttttgcttta gcacttggcc ccattgtaga ttgccctgtg cagtaaactt tcaaggtgtc 1201 ggctgcccca gattgcttca tttgctgggt gtggaaagag ttgctatggc caggcatatg 1261 ggatttggaa gctcagcaga agtgacttct gctctgtggt tgctgctccc cggctttcac 1321 agacatggta tggcagccat tcttttatct atttaaccaa gaggatgctg gggaattgtg 1381 ctgcttgtcc tgttggctgg tggctgcatt atgtcctggg gtgtgcatgt gggtctattt 1441 agagcttctg tcccttcctt cccattgcaa gttgcaccca gatgagacag ctgtagtact 1501 aggtctcttt cacctctcat tgcctgtccc tgcttcgagc tggttgtctt gtgcgtggga 1561 catgggcctt cctatctgtg ttttctcaaa gtcaggagct gaccaggagc acactaaggt 1621 gtggtcatgc atcataacca acattcactc atctgggaca ttcttaagat acatttataa 1681 atcatttcag cagtagtact ttgtatgtgt tgagagttta cagagctctt tgacatacgc 1741 gatcttagtc tttacaaata aggaaaacag ctcagtttgg gaagtatcag agatgggatt 1801 caaacccaga tcctctggtc caagttgtat gtgcactgaa ctaatcaggc aggaaaaaag 1861 cccagccact gtctcacaga ttgttttttg tatattgtag caaaatcctg aaacaatggg 1921 gtccttccag tctcatcata caaaatggca atcttggctg ggtgcggtgg ttcatgccta 1981 taatcccagt gctttacaag gctgaggcag gaggctctct tgagaatagg agttcaagac 2041 cagcctgggc aacatagcaa gatcctgtct ctccaaaaaa aaaaaaaaaa aaaaaaaaaa 2101 atttcatttt tgagtccaga ggaccctcct attactcttg atttcatctt cagagtgtag 2161 ttaaaaaatt attttaaata attatttttt taaatcagtt gtaggttcac agcaaaagtg 2221 gacaaaaaga aatttctcat atatcccctg ccctcacaca tgcatagcct cccaccacta 2281 tcagtatccc acaccagagt ggtacatttg ttacaatcaa taaacctcca ttgacacatc 2341 attatcaccc aaagtccata gtttacatga agattcactc tggtgttgta cattgtatgg 2401 gcttagacaa atgtatgatg atatctacaa ttatagaatc atacagaata gtttcactgc 2461 cctaaaactt ctctatgctt cacctgttca tccctttctt ccctaatccc ctggcaacca 2521 ctttaaaaaa aaaattaggt tcagggggta catgtgcagg taaactcgtg acaagggggt 2581 ttgttataca gattatttag tgacccaggt actaagccta gtacccaata gttacttttc 2641 tggtcctgtc ccttttccca ccctccaccc tcaggtaggc cccagtatgt tattcctttg 2701 tgtccatgtt atttcactcc cacttgtgag aacatggaat atttggtttc ctgttcctat 2761 gttagtttgt taaggataat ggcctccagc cccatccatg ttcctgcaaa ggacatgatc 2821 tttctttggc aaccactttt tactgtcgcc atagttcttc cttttctaga atgtcatatt 2881 ggaatcatat agtatgtagc cttttcagac tggcttcttt cacttaataa tatgcaatta 2941 aggttcctcc atgtcatttc atggcttaat agtgcattta tttttagcac tgaataatac 3001 tccattgtct agatgaatag tttatccatt cacctattga aagacttctt ggtggtttcc 3061 aagttttggc aattatgaat aaagctgttg taaacatctt tgtgcaggtt tttctatggg 3121 catgttttta attcatttga ataaatacca agagcttcag tgctggatca taaa

Nucleic acid encoding a GAP43 sequence (Genbank NM_(—)002045):

(SEQ ID NO: 56) 387                             ATGC TGTGCTGTAT GAGAAGAACC AAACAGGTTG 421 AAAAAAATGA TGACGACCAA AAGATTGAAC AAGATGGTAT CAAACCAGAA GATAAAGCTC 481 ATAAGGCCGC AACCAAAATT CAGGCTAGCT TCCGTGGACA CATAACAAGG AAAAAGCTCA 541 AAGGAGAGAA GAAGGATGAT GTCCAAGCTG CTGAGGCTGA AGCTAATAAG AAGGATGAAG 601 CCCCTGTTGC CGATGGGGTG GAGAAGAAGG GAGAAGGCAC CACTACTGCC GAAGCAGCCC 661 CAGCCACTGG CTCCAAGCCT GATGAGCCCG GCAAAGCAGG AGAAACTCCT TCCGAGGAGA 721 AGAAGGGGGA GGGTGATGCT GCCACAGAGC AGGCAGCCCC CCAGGCTCCT GCATCCTCAG 781 AGGAGAAGGC CGGCTCAGCT GAGACAGAAA GTGCCACTAA AGCTTCCACT GATAACTCGC 841 CGTCCTCCAA GGCTGAAGAT GCCCCAGCCA AGGAGGAGCC TAAACAAGCC GATGTGCCTG 901 CTGCTGTCAC TGCTGCTGCT GCCACCACCC CTGCCGCAGA GGATGCTGCT GCCAAGGCAA 961 CAGCCCAGCC TCCAACGGAG ACTGGGGAGA GCAGCCAAGC TGAAGAGAAC ATAGAAGCTG 1021 TAGATGAAAC CAAACCTAAG GAAAGTGCCC GGCAGGACGA GGGTAAAGAA GAGGAACCTG 1081 AGGCTGACCA AGAACATGCC TGAactctaa gaaatggctt tccacatccc caccctcccc 1141 tctcctgagc ctgtctctcc ctaccctctt ctcagctcca ctctgaagtc ccttcctgtc 1201 ctgctcacgt ctgtgagtct gtcctttccc acccactagc cctctttctc tctgtgtggc 1261 aaacatttaa aaaaaaaaaa aaaaagcagg aaagatccca agtcaaacag tgtggcttaa 1321 acattttttg tttcttggtg ttgttatggc aagtttttgg taatgatgat tcaatcattt 1381 tgggaaattc ttgcactgta tccaagttat ttgatctggt gcgtgtggcc ctgtgggagt 1441 ccactttcct ctctctctct ctctctgttc caagtgtgtg tgcaatgttc cgttcatctg 1501 aggagtccaa aatatcgagt gaattcaaaa tcatttttgt tttcctcctt ttcaatgtga 1561 tggaatgaac aaaaaggaaa aaattcaaaa aacccagttt gttttaaaaa taaataaata 1621 aagcaaatgt gccaattagc gtaaacttgc ggctctaagg ctcctttttc aacccgaata 1681 ttaataaatc atgagagtaa tcaaggtcaa aaaaaaaaaa aaaaaaaaaa aaaaaaaaaa 1741 aaaaaaa

Nucleic acid encoding a CAP23 sequence (Genbank NM_(—)006317):

(SEQ ID NO: 57) 180                                                                 A 181 TGGGAGGCAA GCTCAGCAAG AAGAAGAAGG GCTACAATGT GAACGACGAG AAAGCCAAGG 241 AGAAAGACAA GAAGGCCGAG GGCGCGGCGA CGGAAGAGGA GGGGACCCCG AAGGAGAGTG 301 AGCCCCAGGC GGCCGCAGAG CCCGCCGAGG CCAAGGAGGG CAAGGAGAAG CCCGACCAGG 361 ACGCCGAGGG CAAGGCCGAG GAGAAGGAGG GCGAGAAGGA CGCGGCGGCT GCCAAGGAGG 421 AGGCCCCGAA GGCGGAGCCC GAGAAGACGG AGGGCGCGGC AGAGGCCAAG GCTGAGCCCC 481 CGAAGGCGCC CGAGCAGGAG CAGGCGGCCC CCGGCCCCGC TGCGGGCGGC GAGGCCCCCA 541 AAGCTGCTGA GGCCGCCGCG GCCCCGGCCG AGAGCGCGGC CCCTGCCGCC GGGGAGGAGC 601 CCAGCAAGGA GGAAGGGGAA CCCAAAAAGA CTGAGGCGCC CGCAGCTCCT GCCGCCCAGG 661 AGACCAAAAG TGACGGGGCC CCAGCTTCAG ACTCAAAACC CGGCAGCTCG GAGGCTGCCC 721 CCTCTTCCAA GGAGACCCCC GCAGCCACGG AAGCGCCTAG TTCCACACCC AAGGCCCAGG 781 GCCCCGCAGC CTCTGCAGAA GAGCCCAAGC CGGTGGAGGC CCCGGCAGCT AATTCCGACC 841 AAACCGTAAC CGTGAAAGAG TGAcaaggac agcctatagg aaaaacaata ccacttaaaa 901 caatctcctc tctctctctc tctctctctc tctatctctc tctctatctc ctctctctct 961 ctcctctcct atctctcctc tctctctctc ctatactaac ttgtttcaaa ttggaagtaa 1021 tgatatgtat tgcccaagga aaaatacagg atgttgtccc atcaagggag ggagggggtg 1081 ggagaatcca aatagtattt ttgtggggaa atatctaata taccttcagt caactttacc 1141 aagaagtcct ggatttccaa gatccgcgtc tgaaagtgca gtacatcgtt tgtacctgaa 1201 actgccgcca catgcactcc tccaccgctg agagttgaat agcttttctt ctgcaatggg 1261 agttgggagt gatgcgtttg attctgccca cagggcctgt gccaaggcaa tcagatcttt 1321 atgagagcag tattttctgt gttttctttt taatttacag cctttcttat tttgatattt 1381 ttttaatgtt gtggatgaat gccagctttc agacagagcc cacttagctt gtccacatgg 1441 atctcaatgc caatcctcca ttcttcctct ccagatattt ttgggagtga caaacattct 1501 ctcatcctac ttagcctacc tagatttctc atgacgagtt aatgcatgtc cgtggttggg 1561 tgcacctgta gttctgttta ttggtcagtg gaaatgaaaa aaaaaaaaaa aaaaagtctg 1621 cgttcattgc agttccagtt tctcttccat tctgtgtcac agacaccaac acaccactca 1681 ttggaaaatg gaaaaaaaaa acaaaaaaaa aacaaaaaaa tgtacaatgg atgcattgaa 1741 attatatgta attgtataaa tggtgcaaca gtaataaagt taaacaatta aaaagaaaaa 1801 aaaaaaaaaa aaaaaaaaaa

Nucleic acid encoding a brain-derived neurotrophic factor (BDNF) (Genbank X91251):

(SEQ ID NO: 58) 285                                                 ATGACC ATCCTTTTCC 301 TTACTATGGT TATTTCATAC TTTGGTTGCA TGAAGGCTGC CCCCATGAAA GAAGCAAACA 361 TCCGAGGACA AGGTGGCTTG GCCTACCCAG GTGTGCGGAC CCATGGGACT CTGGAGAGCG 421 TGAATGGGCC CAAGGCAGGT TCAAGAGGCT TGACATCATT GGCTGACACT TTCGAACACG 481 TGATAGAAGA GCTGTTGGAT GAGGACCATA AAGTTCGGCC CAATGAAGAA AACAATAAGG 541 ACGCAGACTT GTACACGTCC AGGGTGATGC TCAGTAGTCA AGTGCCTTTG GAGCCTCCTC 601 TTCTCTTTCT GCTGGAGGAA TACAAAAATT ACCTAGATGC TGCAAACATG TCCATGATGG 661 TCCTGCGCCA CTCTGACCCT GCCCGCCGAG GGGAGCTGAG CGTGTGTGAC AGTATTAGTG 721 AGTGGGTAAC GGCGGCAGAC AAAAAGACTG CAGTGGACAT GTCGGGCGGG ACGGTCACAG 781 TCCTTGAAAA GGTCCCTGTA TCAAAAGGCC AACTGAAGCA ATACTTCTAC GAGACCAAGT 841 GCAATCCCAT GGGTTACACA AAAGAAGGCT GCAGGGGCAT AGACAAAAGG CATTGGAACT 901 CCCAGTGCCG AACTACCCAG TCGTACGTGC GGGCCCTTAC CATGGATAGC AAAAAGAGAA 961 TTGGCTGGCG ATTCATAAGG ATAGACACTT CTTGTGTATG TACATTGACC ATTAAAAGGG 1021 GAAGATAGtg gatttatgtt gtatagatta gattatattg agacaaaaat tatctatttg 1081 tatatataca taacagggta aattattcag ttaagaaaaa aataatttta ttaactgcat 1141 gtataaatga agtttataca gtacagtggt tctacaatct atttattgga catgtccatg 1201 accagaaggg aaacagtcat ttgcgcacaa cttaaaaagt ctgcattaca ttccttgata 1261 atgttgtggt ttgttgccgt tgccaagaac tgaaaacata aaaatttaaa aaaaataatc 1321 ccttgcatgc tgccc

Nucleic acid encoding neurotrophin-3 (NT-3) (Genbank BC107075):

(SEQ ID NO: 59) 71            ATGTCCATCT TGTTTTATGT GATATTTCTC GCTTATCTCC GTGGCATCCA 121 AGGTAACAAC ATGGATCAAA GGAGTTTGCC AGAAGACTCG CTCAATTCCC TCATTATTAA 181 GCTGATCCAG GCAGATATTT TGAAAAACAA GCTCTCCAAG CAGATGGTGG ACGTTAAGGA 241 AAATTACCAG AGCACCCTGC CCAAAGCTGA GGCTCCCCGA GAGCCGGAGC GGGGAGGGCC 301 CGCCAAGTCA GCATTCCAGC CAGTGATTGC AATGGACACC GAACTGCTGC GACAACAGAG 361 ACGCTACAAC TCACCGCGGG TCCTGCTGAG CGACAGCACC CCCTTGGAGC CCCCGCCCTT 421 GTATCTCATG GAGGATTACG TGGGCAGCCC CGTGGTGGCG AACAGAACAT CACGGCGGAA 481 ACGGTACGCG GAGCATAAGA GTCACCGAGG GGAGTACTCG GTATGTGACA GTGAGAGTCT 541 GTGGGTGACC GACAAGTCAT CGGCCATCGA CATTCGGGGA CACCAGGTCA CGGTGCTGGG 601 GGAGATCAAA ACGGGCAACT CTCCTGTCAA ACAATATTTT TATGAAACGC GATGTAAGGA 661 AGCCAGGCCG GTCAAAAACG GTTGCAGGGG TATTGATGAT AAACACTGGA ACTCTCAGTG 721 CAAAACATCC CAAACCTACG TCCGAGCACT GACTTCAGAG AACAATAAAC TCGTGGGCTG 781 GCGGTGGATA CGGATAGACA CGTCCTGTGT GTGTGCCTTG TCGAGAAAAA TCGGAAGAAC 841 ATGAattggc atctctcccc atatataaat tattacttta aattatatga tatgcatgta 901 gcatataaat gtttatattg tttttatata ttataagttg acctttattt attaaacttc 961 agcaacccta cagtatataa gcttttttct caataaaatc agtgtgcttg ccttccctca 1021 ggcctctccc atct

A nucleic acid encoding a glial-derived neurotropic factor (GDNF) (Genbank NM_(—)000514):

(SEQ ID NO: 60) 201                       ATGAAGTTAT GGGATGTCGT GGCTGTCTGC CTGGTGCTGC 241 TCCACACCGC GTCCGCCTTC CCGCTGCCCG CCGGTAAGAG GCCTCCCGAG GCGCCCGCCG 301 AAGACCGCTC CCTCGGCCGC CGCCGCGCGC CCTTCGCGCT GAGCAGTGAC TCAAATATGC 361 CAGAGGATTA TCCTGATCAG TTCGATGATG TCATGGATTT TATTCAAGCC ACCATTAAAA 421 GACTGAAAAG GTCACCAGAT AAACAAATGG CAGTGCTTCC TAGAAGAGAG CGGAATCGGC 481 AGGCTGCAGC TGCCAACCCA GAGAATTCCA GAGGAAAAGG TCGGAGAGGC CAGAGGGGCA 541 AAAACCGGGG TTGTGTCTTA ACTGCAATAC ATTTAAATGT CACTGACTTG GGTCTGGGCT 601 ATGAAACCAA GGAGGAACTG ATTTTTAGGT ACTGCAGCGG CTCTTGCGAT GCAGCTGAGA 661 CAACGTACGA CAAAATATTG AAAAACTTAT CCAGAAATAG AAGGCTGGTG AGTGACAAAG 721 TAGGGCAGGC ATGTTGCAGA CCCATCGCCT TTGATGATGA CCTGTCGTTT TTAGATGATA 781 ACCTGGTTTA CCATATTCTA AGAAAGCATT CCGCTAAAAG GTGTGGATGT ATCTGA

Any of the above sequences could be expressed in an axon of a mammalian cell when operably linked to an IRES sequence. Coding sequences for polypeptides of interest can be at any distance downstream of the IRES sequences. For example, a polypeptide-coding sequence can be within 10 nucleotides, e.g. within 8, 6, 4 or fewer nucleotides, of the 3′ end of an IRES. Coding sequences can also be as distant as about 200 to 300 or more nucleotides away from the 3′ end of IRES. In general, translation begins at the first start codon, e.g. ATG, GTG, ATT, downstream, i.e. 3′, of an IRES.

Viruses of the Invention

The invention provides recombinant RNA viruses and pseudo-viruses that can be used to deliver selected polypeptide-coding sequences into the axons of mammalian neurons for expression of the encoded polypeptides in the axons. Thus, a virus of the invention contains a recombinant RNA molecule of the invention and is capable of transducing the RNA molecule into an axon of a mammalian neuron.

A virus of the invention can be recombinant RNA virus, as well as a pseudo-virus. A pseudovirus or pseudo-viral particle differs from a recombinant RNA virus of the invention in that the genome of the pseudo-virus or viral particle lacks one or more coding sequences required to generate viral particles upon infection of a mammalian host cell.

A virus of the invention can be any single-stranded RNA virus that can infect a mammalian cell, or which can selectively infect neurons or neuronal subtypes, or which may selectively infect axons. For example, a virus of the invention can be an alphavirus, a virus of the group IV Togaviridae family of viruses. Non-limiting examples of alphaviruses include such as a Sindbis virus or a Semliki Forest virus. A virus of the invention can be an attenuated form of an alphavirus that is less cytotoxic to a mammalian cell.

A virus of the invention can be formulated as a pharmaceutical composition for administration to a mammal as discussed below.

Methods of Generating Nucleic Acids and Viruses of the Invention

Recombinant nucleic acid molecules, as well as viruses of the invention can be produced using methods known to those of skill in the art. See, for example, the methods described MOLECULAR CLONING: A LABORATORY MANUAL, Sambrook & Russell eds., Cold Spring Harbor Laboratory Press, Cold Spring Harbor, N.Y. (2001) [hereinafter MOLECULAR CLONING] or CURRENT PROTOCOLS IN MOLECULAR BIOLOGY, eds. Ausubel et al., John Wiley & Sons, Inc. (1994) [hereinafter CURRENT PROTOCOLS]. Briefly, a coding sequence for a selected polypeptide can be cloned into a DNA expression vector, which serves as a template from which the recombinant RNA molecule of the invention can be generated by in vitro transcription. The expression vector includes sequences coding for a viral replicase, a promoter for subgenomic transcription operably-linked to a sequence that encode the selected polypeptide. Alternatively, the RNA molecule can be produced by in vivo transcription from a DNA plasmid or from a DNA sequence that is stably integrated in the genome of a suitable mammalian host cell.

Recombinant RNA viruses or pseudo-viruses can be produced by (1) transfecting a suitable mammalian host cell with a recombinant RNA molecule of the invention or (2) expressing the recombinant RNA molecule of the invention from a DNA expression vector or from a DNA sequence that is stably integrated in the genome of a suitable mammalian host cell. Where the recombinant RNA molecule does not encode one or more viral proteins required for viral packaging and assembly, a helper RNA molecule having sequences that encode viral structural proteins required for viral assembly can be co-transfected. Alternatively, a helper virus can be used to infect the host cell and provide the sequences for expression of viral proteins required for viral packaging and assembly.

Any mammalian host cell can be used for the in vivo packaging of recombinant RNA molecules of the invention. Non-limiting examples include BHK-21 cells and 293 cells. Viruses so prepared can be purified using methods known to those of skill in the art. Methods for the (1) preparation, enzymatic manipulation and analysis of DNA and RNA nucleic acids; (2) construction, screening and analysis of recombinant nucleic acid vectors; and (3) introduction of DNA and RNA into mammalian cells such as electroporation, transfection (e.g. liposome mediated), and transduction are known to those of skill in the art. See MOLECULAR CLONING; see also CURRENT PROTOCOLS. See also Frolov et al., Proc. Natl. Acad. Sci. USA, 93:11371-11377 (1996); Pekosz et al., Proc. Natl. Acad. Sci. USA 96:8804-8806 (1999) & Wu et al., Nature 436: 1020-1024 and accompanying supplemental materials (2005).

An example of a method for the production of nucleic acids and viruses that can be used to express a mammalian protein in the axon of a mammalian neuron is described below. Additional nucleic acids and methods for generating the nucleic acids of the invention are described in U.S. Pat. Nos. 6,451,592; 6458,560; & 6,465,634, as well as U.S. Patent Application No. 2007/0166820.

Sindbis virus is a (+)-strand RNA virus, and can be generated with coat proteins that allow the transduction of an mRNA into cells including neurons. The viral genome contains a subgenomic promoter from which a second mRNA encoding the gene of interest can transcribed. To produce a recombinant RNA molecule from which a select polypeptide can be expressed in the axon of a mammalian neuron, pSinRep5, a DNA expression vector that encodes the genome of an attenuated form of Sindbis virus can be used. A schematic diagram of the structure of pSinRep5 is shown in FIG. 15. An IRES sequence can be inserted into the pSinRep5 vector at the XbaI-MluI restriction site. A schematic diagram of the resulting expression vector is shown in FIG. 16. The full-length sequence of the pSinRep5-IRES is shown below, in which restriction enzyme sites are bolded, IRES is shown in capital letters and the ATG start codon underlined.

(SEQ ID NO: 61) 1 cgcgtagatc tcacgtgagc atgcaggcct tgggcccaat gatccgacca 51 gcaaaactcg atgtacttcc gaggaactga tgtgcataat gcatcaggct 101 ggtacattag atccccgctt accgcgggca atatagcaac actaaaaact 151 cgatgtactt ccgaggaagc gcagtgcata atgctgcgca gtgttgccac 201 ataaccacta tattaaccat ttatctagcg gacgccaaaa actcaatgta 251 tttctgagga agcgtggtgc ataatgccac gcagcgtctg cataactttt 301 attatttctt ttattaatca acaaaatttt gtttttaaca tttcaaaaaa 351 aaaaaaaaaa aaaaaaaaaa aaaaaaaaaa agggaattcc tcgattaatt 401 aagcggccgc tcgaggggaa ttaattcttg aagacgaaag ggccaggtgg 451 cacttttcgg ggaaatgtgc gcggaacccc tatttgttta tttttctaaa 501 tacattcaaa tatgtatccg ctcatgagac aataaccctg ataaatgctt 551 caataatatt gaaaaaggaa gagtatgagt attcaacatt tccgtgtcgc 601 ccttattccc ttttttgcgg cattttgcct tcctgttttt gctcacccag 651 aaacgctggt gaaagtaaaa gatgctgaag atcagttggg tgcacgagtg 701 ggttacatcg aactggatct caacagcggt aagatccttg agagttttcg 751 ccccgaagaa cgttttccaa tgatgagcac ttttaaagtt ctgctatgtg 801 gcgcggtatt atcccgtgtt gacgccgggc aagagcaact cggtcgccgc 851 atacactatt ctcagaatga cttggttgag tactcaccag tcacagaaaa 901 gcatcttacg gatggcatga cagtaagaga attatgcagt gctgccataa 951 ccatgagtga taacactgcg gccaacttac ttctgacaac gatcggagga 1001 ccgaaggagc taaccgcttt tttgcacaac atgggggatc atgtaactcg 1051 ccttgatcgt tgggaaccgg agctgaatga agccatacca aacgacgagc 1101 gtgacaccac gatgcctgta gcaatggcaa caacgttgcg caaactatta 1151 actggcgaac tacttactct agcttcccgg caacaattaa tagactggat 1201 ggaggcggat aaagttgcag gaccacttct gcgctcggcc cttccggctg 1251 gctggtttat tgctgataaa tctggagccg gtgagcgtgg gtctcgcggt 1301 atcattgcag cactggggcc agatggtaag ccctcccgta tcgtagttat 1351 ctacacgacg gggagtcagg caactatgga tgaacgaaat agacagatcg 1401 ctgagatagg tgcctcactg attaagcatt ggtaactgtc agaccaagtt 1451 tactcatata tactttagat tgatttaaaa cttcattttt aatttaaaag 1501 gatctaggtg aagatccttt ttgataatct catgaccaaa atcccttaac 1551 gtgagttttc gttccactga gcgtcagacc ccgtagaaaa gatcaaagga 1601 tcttcttgag atcctttttt tctgcgcgta atctgctgct tgcaaacaaa 1651 aaaaccaccg ctaccagcgg tggtttgttt gccggatcaa gagctaccaa 1701 ctctttttcc gaaggtaact ggcttcagca gagcgcagat accaaatact 1751 gtccttctag tgtagccgta gttaggccac cacttcaaga actctgtagc 1801 accgcctaca tacctcgctc tgctaatcct gttaccagtg gctgctgcca 1851 gtggcgataa gtcgtgtctt accgggttgg actcaagacg atagttaccg 1901 gataaggcgc agcggtcggg ctgaacgggg ggttcgtgca cacagcccag 1951 cttggagcga acgacctaca ccgaactgag atacctacag cgtgagcatt 2001 gagaaagcgc cacgcttccc gaagggagaa aggcggacag gtatccggta 2051 agcggcaggg tcggaacagg agagcgcacg agggagcttc cagggggaaa 2101 cgcctggtat ctttatagtc ctgtcgggtt tcgccacctc tgacttgagc 2151 gtcgattttt gtgatgctcg tcaggggggc ggagcctatg gaaaaacgcc 2201 agcaacgcga gctcgtatgg acatattgtc gttagaacgc ggctacaatt 2251 aatacataac cttatgtatc atacacatac gatttagggg acactataga 2301 ttgacggcgt agtacacact attgaatcaa acagccgacc aattgcacta 2351 ccatcacaat ggagaagcca gtagtaaacg tagacgtaga cccccagagt 2401 ccgtttgtcg tgcaactgca aaaaagcttc ccgcaatttg aggtagtagc 2451 acagcaggtc actccaaatg accatgctaa tgccagagca ttttcgcatc 2501 tggccagtaa actaatcgag ctggaggttc ctaccacagc gacgatcttg 2551 gacataggca gcgcaccggc tcgtagaatg ttttccgagc accagtatca 2601 ttgtgtctgc cccatgcgta gtccagaaga cccggaccgc atgatgaaat 2651 acgccagtaa actggcggaa aaagcgtgca agattacaaa caagaacttg 2701 catgagaaga ttaaggatct ccggaccgta cttgatacgc cggatgctga 2751 aacaccatcg ctctgctttc acaacgatgt tacctgcaac atgcgtgccg 2801 aatattccgt catgcaggac gtgtatatca acgctcccgg aactatctat 2851 catcaggcta tgaaaggcgt gcggaccctg tactggattg gcttcgacac 2901 cacccagttc atgttctcgg ctatggcagg ttcgtaccct gcgtacaaca 2951 ccaactgggc cgacgagaaa gtccttgaag cgcgtaacat cggactttgc 3001 agcacaaagc tgagtgaagg taggacagga aaattgtcga taatgaggaa 3051 gaaggagttg aagcccgggt cgcgggttta tttctccgta ggatcgacac 3101 tttatccaga acacagagcc agcttgcaga gctggcatct tccatcggtg 3151 ttccacttga atggaaagca gtcgtacact tgccgctgtg atacagtggt 3201 gagttgcgaa ggctacgtag tgaagaaaat caccatcagt cccgggatca 3251 cgggagaaac cgtgggatac gcggttacac acaatagcga gggcttcttg 3301 ctatgcaaag ttactgacac agtaaaagga gaacgggtat cgttccctgt 3351 gtgcacgtac atcccggcca ccatatgcga tcagatgact ggtataatgg 3401 ccacggatat atcacctgac gatgcacaaa aacttctggt tgggctcaac 3451 cagcgaattg tcattaacgg taggactaac aggaacacca acaccatgca 3501 aaattacctt ctgccgatca tagcacaagg gttcagcaaa tgggctaagg 3551 agcgcaagga tgatcttgat aacgagaaaa tgctgggtac tagagaacgc 3601 aagcttacgt atggctgctt gtgggcgttt cgcactaaga aagtacattc 3651 gttttatcgc ccacctggaa cgcagacctg cgtaaaagtc ccagcctctt 3701 ttagcgcttt tcccatgtcg tccgtatgga cgacctcttt gcccatgtcg 3751 ctgaggcaga aattgaaact ggcattgcaa ccaaagaagg aggaaaaact 3801 gctgcaggtc tcggaggaat tagtcatgga ggccaaggct gcttttgagg 3851 atgctcagga ggaagccaga gcggagaagc tccgagaagc acttccacca 3901 ttagtggcag acaaaggcat cgaggcagcc gcagaagttg tctgcgaagt 3951 ggaggggctc caggcggaca tcggagcagc attagttgaa accccgcgcg 4001 gtcacgtaag gataatacct caagcaaatg accgtatgat cggacagtat 4051 atcgttgtct cgccaaactc tgtgctgaag aatgccaaac tcgcaccagc 4101 gcacccgcta gcagatcagg ttaagatcat aacacactcc ggaagatcag 4151 gaaggtacgc ggtcgaacca tacgacgcta aagtactgat gccagcagga 4201 ggtgccgtac catggccaga attcctagca ctgagtgaga gcgccacgtt 4251 agtgtacaac gaaagagagt ttgtgaaccg caaactatac cacattgcca 4301 tgcatggccc cgccaagaat acagaagagg agcagtacaa ggttacaaag 4351 gcagagcttg cagaaacaga gtacgtgttt gacgtggaca agaagcgttg 4401 cgttaagaag gaagaagcct caggtctggt cctctcggga gaactgacca 4451 accctcccta tcatgagcta gctctggagg gactgaagac ccgacctgcg 4501 gtcccgtaca aggtcgaaac aataggagtg ataggcacac cggggtcggg 4551 caagtcagct attatcaagt caactgtcac ggcacgagat cttgttacca 4601 gcggaaagaa agaaaattgt cgcgaaattg aggccgacgt gctaagactg 4651 aggggtatgc agattacgtc gaagacagta gattcggtta tgctcaacgg 4701 atgccacaaa gccgtagaag tgctgtacgt tgacgaagcg ttcgcgtgcc 4751 acgcaggagc actacttgcc ttgattgcta tcgtcaggcc ccgcaagaag 4801 gtagtactat gcggagaccc catgcaatgc ggattcttca acatgatgca 4851 actaaaggta catttcaatc accctgaaaa agacatatgc accaagacat 4901 tctacaagta tatctcccgg cgttgcacac agccagttac agctattgta 4951 tcgacactgc attacgatgg aaagatgaaa accacgaacc cgtgcaagaa 5001 gaacattgaa atcgatatta caggggccac aaagccgaag ccaggggata 5051 tcatcctgac atgtttccgc gggtgggtta agcaattgca aatcgactat 5101 cccggacatg aagtaatgac agccgcggcc tcacaagggc taaccagaaa 5151 aggagtgtat gccgtccggc aaaaagtcaa tgaaaaccca ctgtacgcga 5201 tcacatcaga gcatgtgaac gtgttgctca cccgcactga ggacaggcta 5251 gtgtggaaaa ccttgcaggg cgacccatgg attaagcagc ccactaacat 5301 acctaaagga aactttcagg ctactataga ggactgggaa gctgaacaca 5351 agggaataat tgctgcaata aacagcccca ctccccgtgc caatccgttc 5401 agctgcaaga ccaacgtttg ctgggcgaaa gcattggaac cgatactagc 5451 cacggccggt atcgtactta ccggttgcca gtggagcgaa ctgttcccac 5501 agtttgcgga tgacaaacca cattcggcca tttacgcctt agacgtaatt 5551 tgcattaagt ttttcggcat ggacttgaca agcggactgt tttctaaaca 5601 gagcatccca ctaacgtacc atcccgccga ttcagcgagg ccggtagctc 5651 attgggacaa cagcccagga acccgcaagt atgggtacga tcacgccatt 5701 gccgccgaac tctcccgtag atttccggtg ttccagctag ctgggaaggg 5751 cacacaactt gatttgcaga cggggagaac cagagttatc tctgcacagc 5801 ataacctggt cccggtgaac cgcaatcttc ctcacgcctt agtccccgag 5851 tacaaggaga agcaacccgg cccggtcaaa aaattcttga accagttcaa 5901 acaccactca gtacttgtgg tatcagagga aaaaattgaa gctccccgta 5951 agagaatcga atggatcgcc ccgattggca tagccggtgc agataagaac 6001 tacaacctgg ctttcgggtt tccgccgcag gcacggtacg acctggtgtt 6051 catcaacatt ggaactaaat acagaaacca ccactttcag cagtgcgaag 6101 accatgcggc gaccttaaaa accctttcgc gttcggccct gaattgcctt 6151 aacccaggag gcaccctcgt ggtgaagtcc tatggctacg ccgaccgcaa 6201 cagtgaggac gtagtcaccg ctcttgccag aaagtttgtc agggtgtctg 6251 cagcgagacc agattgtgtc tcaagcaata cagaaatgta cctgattttc 6301 cgacaactag acaacagccg tacacggcaa ttcaccccgc accatctgaa 6351 ttgcgtgatt tcgtccgtgt atgagggtac aagagatgga gttggagccg 6401 cgccgtcata ccgcaccaaa agggagaata ttgctgactg tcaagaggaa 6451 gcagttgtca acgcagccaa tccgctgggt agaccaggcg aaggagtctg 6501 ccgtgccatc tataaacgtt ggccgaccag ttttaccgat tcagccacgg 6551 agacaggcac cgcaagaatg actgtgtgcc taggaaagaa agtgatccac 6601 gcggtcggcc ctgatttccg gaagcaccca gaagcagaag ccttgaaatt 6651 gctacaaaac gcctaccatg cagtggcaga cttagtaaat gaacataaca 6701 tcaagtctgt cgccattcca ctgctatcta caggcattta cgcagccgga 6751 aaagaccgcc ttgaagtatc acttaactgc ttgacaaccg cgctagacag 6801 aactgacgcg gacgtaacca tctattgcct ggataagaag tggaaggaaa 6851 gaatcgacgc ggcactccaa cttaaggagt ctgtaacaga gctgaaggat 6901 gaagatatgg agatcgacga tgagttagta tggattcatc cagacagttg 6951 cttgaaggga agaaagggat tcagtactac aaaaggaaaa ttgtattcgt 7001 acttcgaagg caccaaattc catcaagcag caaaagacat ggcggagata 7051 aaggtcctgt tccctaatga ccaggaaagt aatgaacaac tgtgtgccta 7101 catattgggt gagaccatgg aagcaatccg cgaaaagtgc ccggtcgacc 7151 ataacccgtc gtctagcccg cccaaaacgt tgccgtgcct ttgcatgtat 7201 gccatgacgc cagaaagggt ccacagactt agaagcaata acgtcaaaga 7251 agttacagta tgctcctcca ccccccttcc taagcacaaa attaagaatg 7301 ttcagaaggt tcagtgcacg aaagtagtcc tgtttaatcc gcacactccc 7351 gcattcgttc ccgcccgtaa gtacatagaa gtgccagaac agcctaccgc 7401 tcctcctgca caggccgagg aggcccccga agttgtagcg acaccgtcac 7451 catctacagc tgataacacc tcgcttgatg tcacagacat ctcactggat 7501 atggatgaca gtagcgaagg ctcacttttt tcgagcttta gcggatcgga 7551 caactctatt actagtatgg acagttggtc gtcaggacct agttcactag 7601 agatagtaga ccgaaggcag gtggtggtgg ctgacgttca tgccgtccaa 7651 gagcctgccc ctattccacc gccaaggcta aagaagatgg cccgcctggc 7701 agcggcaaga aaagagccca ctccaccggc aagcaatagc tctgagtccc 7751 tccacctctc ttttggtggg gtatccatgt ccctcggatc aattttcgac 7801 ggagagacgg cccgccaggc agcggtacaa cccctggcaa caggccccac 7851 ggatgtgcct atgtctttcg gatcgttttc cgacggagag attgatgagc 7901 tgagccgcag agtaactgag tccgaacccg tcctgtttgg atcatttgaa 7951 ccgggcgaag tgaactcaat tatatcgtcc cgatcagccg tatcttttcc 8001 actacgcaag cagagacgta gacgcaggag caggaggact gaatactgac 8051 taaccggggt aggtgggtac atattttcga cggacacagg ccctgggcac 8101 ttgcaaaaga agtccgttct gcagaaccag cttacagaac cgaccttgga 8151 gcgcaatgtc ctggaaagaa ttcatgcccc ggtgctcgac acgtcgaaag 8201 aggaacaact caaactcagg taccagatga tgcccaccga agccaacaaa 8251 agtaggtacc agtctcgtaa agtagaaaat cagaaagcca taaccactga 8301 gcgactactg tcaggactac gactgtataa ctctgccaca gatcagccag 8351 aatgctataa gatcacctat ccgaaaccat tgtactccag tagcgtaccg 8401 gcgaactact ccgatccaca gttcgctgta gctgtctgta acaactatct 8451 gcatgagaac tatccgacag tagcatctta tcagattact gacgagtacg 8501 atgcttactt ggatatggta gacgggacag tcgcctgcct ggatactgca 8551 accttctgcc ccgctaagct tagaagttac ccgaaaaaac atgagtatag 8601 agccccgaat atccgcagtg cggttccatc agcgatgcag aacacgctac 8651 aaaatgtgct cattgccgca actaaaagaa attgcaacgt cacgcagatg 8701 cgtgaactgc caacactgga ctcagcgaca ttcaatgtcg aatgctttcg 8751 aaaatatgca tgtaatgacg agtattggga ggagttcgct cggaagccaa 8801 ttaggattac cactgagttt gtcaccgcat atgtagctag actgaaaggc 8851 cctaaggccg ccgcactatt tgcaaagacg tataatttgg tcccattgca 8901 agaagtgcct atggatagat tcgtcatgga catgaaaaga gacgtgaaag 8951 ttacaccagg cacgaaacac acagaagaaa gaccgaaagt acaagtgata 9001 caagccgcag aacccctggc gactgcttac ttatgcggga ttcaccggga 9051 attagtgcgt aggcttacgg ccgtcttgct tccaaacatt cacacgcttt 9101 ttgacatgtc ggcggaggat tttgatgcaa tcatagcaga acacttcaag 9151 caaggcgacc cggtactgga gacggatatc gcatcattcg acaaaagcca 9201 agacgacgct atggcgttaa ccggtctgat gatcttggag gacctgggtg 9251 tggatcaacc actactcgac ttgatcgagt gcgcctttgg agaaatatca 9301 tccacccatc tacctacggg tactcgtttt aaattcgggg cgatgatgaa 9351 atccggaatg ttcctcacac tttttgtcaa cacagttttg aatgtcgtta 9401 tcgccagcag agtactagaa gagcggctta aaacgtccag atgtgcagcg 9451 ttcattggcg acgacaacat catacatgga gtagtatctg acaaagaaat 9501 ggctgagagg tgcgccacct ggctcaacat ggaggttaag atcatcgacg 9551 cagtcatcgg tgagagacca ccttacttct gcggcggatt tatcttgcaa 9601 gattcggtta cttccacagc gtgccgcgtg gcggatcccc tgaaaaggct 9651 gtttaagttg ggtaaaccgc tcccagccga cgacgagcaa gacgaagaca 9701 gaagacgcgc tctgctagat gaaacaaagg cgtggtttag agtaggtata 9751 acaggcactt tagcagtggc cgtgacgacc cggtatgagg tagacaatat 9801 tacacctgtc ctactggcat tgagaacttt tgcccagagc aaaagagcat 9851 tccaagccat cagaggggaa ataaagcatc tctacggtgg tcctaaatag 9901 tcagcatagt acatttcatc tgactaatac tacaacacca ccacctctag 9951 attccGCCCC TCTCCCTCCC CCCCCCCTAA CGTTACTGGC CGAAGCCGCT 10001 TGGAATAAGG CCGGTGTGCG TTTGTCTATA TGTTATTTTC CACCATATTG 10051 CCGTCTTTTG GCAATGTGAG GGCCCGGAAA CCTGGCCCTG TCTTCTTGAC 10101 GAGCATTCCT AGGGGTCTTT CCCCTCTCGC CAAAGGAATG CAAGGTCTGT 10151 TGAATGTCGT GAAGGAAGCA GTTCCTCTGG AAGCTTCTTG AAGACAAACA 10201 ACGTCTGTAG CGACCCTTTG CAGGCAGCGG AACCCCCCAC CTGGCGACAG 10251 GTGCCTCTGC GGCCAAAAGC CACGTGTATA AGATACACCT GCAAAGGCGG 10301 CACAACCCCA GTGCCACGTT GTGAGTTGGA TAGTTGTGGA AAGAGTCAAA 10351 TGGCTCTCCT CAAGCGTATT CAACAAGGGG CTGAAGGATG CCCAGAAGGT 10401 ACCCCATTGT ATGGGATCTG ATCTGGGGCC TCGGTGCACA TGCTTTACAT 10451 GTGTTTAGTC GAGGTTAAAA AAACGTCTAG GCCCCCCGAA CCACGGGGAC 10501 GTGGTTTTCC TTTGAAAAAC ACGatgataa gcttgccaca a

A nucleic acid encoding a selected protein for expression in an axon can be inserted downstream of the IRES sequence, for example, by cloning into the MluI and/or SphI restriction sites shown bolded at nucleotides 10541 & 19 in FIG. 14. Insertion of the sequence encoding the gene of interest can be confirmed by the polymerase chain reaction and sequencing using the following primers: (1) Sindbis forward sequencing primer: 5′-AGCATAGTACATTTCATCTG-3′ (SEQ ID NO: 62); (2) Sindbis reverse sequencing primer: 5′-AAGTACATCGAGTTTTGCTG-3′ (SEQ ID NO: 63); (3) Sindbis reverse sequencing primer 2: 5′-ACCTGGCCCTTTCGTCTTCA-3′ (SEQ ID NO: 64); and (4) IRES sequencing primer: 5′-AACCACGGGGACGTGGTTTTCCTTTGAAA-3′ (SEQ ID NO: 65).

The resulting Sindbis vector can be used as an expression vector for RNA production. For example, the DNA expression vector can be linearized by cleavage using a restriction enzyme such as XhoI. A linear form of the DNA expression vector can then be used as a template in an in vitro transcription step to produce a recombinant RNA molecule that has a 5′CAP structure and a polyA (polyadenylyl) tail. The recombinant RNA molecule is in vitro transcribed from the SP6 promoter of the linearized DNA expression vector.

To produce viral particles carrying the above produced recombinant RNA molecule, in vitro transcribed RNA molecules can be transfected into a suitable mammalian host cell using standard electroporation or other standard means of delivery including liposome-mediated. Alternatively, the covalently-closed circular Sindbis vector can be introduced into a host cell from which viral RNA molecules can be transcribed.

If the recombinant RNA molecule encoded by the DNA expression vector does not encode viral structural genes required for packaging and assembly, e.g. genes that encode the capsid or the glycoproteins E1, E2, D3 and 6K, a helper expression plasmid having genes that encode these proteins can be co-transfected or introduced into the host cell for viral production. An example of a suitable host cell is BHK-1.

BHK-1 cells that have been transfected with the RNA molecule and/or helper plasmid release Sindbis viruses or pseudo-viruses into the cell culture medium. The virus-containing cell culture medium can be used directly, i.e. applied to neurons, or viruses can be harvested and purified using methods known in the art such as, for example, centrifugation in a sucrose step gradient, prior to use.

Methods of the Invention

The invention provides a method of expressing a polypeptide in the axon of a mammalian neuron. The method involves contacting the axon with a virus of the invention under conditions effective for the transduction of the recombinant RNA molecule in the virus into the axon. As discussed herein the recombinant RNA molecule includes a mammalian translation initiation element and a coding sequence for a select polypeptide.

Any polypeptide that can be translated from an RNA transcript can be expressed using a method of the invention. The polypeptide can be one that when expressed in the axon, modulates the growth or function of the axon. As used herein, the term “modulate” means to alter or affect in any amount and includes augmenting or attenuating the growth, regeneration or function of the axon. Non-limiting examples of a polypeptide that can be expressed using a method of the invention include a kinase, a transcription factor, a C3-ADP-ribosyltransferase, a dominant-negative RhoA mutant polypeptide, a cAMP-producing enzyme such as a soluble adenylyl cyclase, glutamic acid decarboxylase, human proenkephalin, an inhibitor of a dominant-negative Vps24, an intestinal peptide (VIP), brain-derived neurotrophic factor (BDNF), neurotrophin-3 (NT-3), glial-derived neurotropic factor (GDNF), GAP 43 and CAP23. Alternatively, the polypeptide to be expressed using a method of the invention can be one that generates a readily detectable signal and therefore function as a reporter for gene expression. Non-limiting examples include green fluorescent protein or Cherry.

Thus, a method of the invention can be used to express a polypeptide such as C3-ADP-ribosyltransferase, an inhibitor of the GTPase RhoA, or a dominant-negative RhoA kinase such as I1009A, both of which would promote axon regeneration and recovery in cases of nerve damage such as in spinal cord injury, laceration or diabetic neuropathy. Similarly, since cyclic AMP can induce axon regeneration, expression of a soluble adenylyl cyclase in the axon of a neuron using a method of the invention can also lead to axon sprouting and regeneration. Expression of glutamic acid decarboxylase (CAD), an enzyme that synthesizes the neurotransmitter gamma-aminobutyric acid (GABA), which act at the terminals of sensory neurons, could be used to suppress activity of the neuron and treat chronic pain such as neuropathic or inflammatory pain.

In addition, expression of proteins that could interfere with maturation and/or release of herpes simplex virus from the axons of infected mammalian cells such as a dominant-negative mutant of the ATPase VPs24 can be useful for the treatment of herpes simplex viral infection. A method of the invention can also be used to examine gene expression in the axon of a neuron.

A method of the invention can be used to express a select polypeptide in the axons of neurons in the central or peripheral nervous system. A method of the invention can be used to express a select polypeptide in the axon of a sensory neuron, a motor neuron or an inter-neuron. As such, a method of the invention can be used to modulate the activity of neurons in the central or peripheral nervous system, and can be used to affect the activity of a sensory neuron, a motor neuron or an inter-neuron.

The method of the invention can also be used to treat a condition associated with aberrant activity in the axon of a neuron. Thus, a method of the invention can be used to treat any other disease or disorder where the injured axon can be specifically located. Such conditions included any axonal injuries or axonal degeneration resulting from laceration, spinal cord injury, other trauma, stroke, or diabetes. Non-limiting examples of diseases or disorders that can be treated using a method of the invention include (1) axonal injuries in the central or peripheral nervous systems; (2) neuropathic or inflammatory pain as well as bone pain; and (3) Herpes simplex viral infections.

In axonal injuries of the central or peripheral nervous systems, expression of proteins that promote axonal growth could improve or hasten functional recovery. For example, expression of proteins that block proteolytic enzymes or Na⁺ and Ca²⁺ channels can prevent damage due to the influx of Ca²⁺ that occurs during inflammation or during axonal degeneration. In addition, damage to axons often occurs as a result of a cascade of events and biological pathways, with one element of the process activating the next. Thus, a single inhibitor of one part of a cascade may thereby block all of the products downstream from it (Arundine et al., Journal of Neuroscience 24(37): 8106-8123 (2004)). Intestinal peptide (VIP) is one example of an inhibitor that may be used to treat axonal injuries. VIP increases the breakdown of glycogen by astrocytes, diminishes the inflammatory response, and may promote the differentiation of oligodendrocyte precursors by agonizing prolactin secretion. Another example is nerve growth factor (NGF).

In chronic pain such as neuropathic pain, inflammatory pain (including arthritis) and bone pain associated with cancer,_proteins or peptides that act at the nerve terminals of sensory neurons are useful therapeutic candidates. Non-limiting examples include glutamic acid decarboxylase (GAD), an enzyme that synthesizes the neurotransmitter gamma-aminobutyric acid (GABA), which suppresses activity in nerve cells (Hao et al., Annals of Neurology, 57: 914-918, 2005) and human proenkephalin, an endogenous opioid peptide with antihyperalgesic properties (Wilson, et al., PNAS, 96: 3211-3216, 1999).

For treatment of herpes simplex viral infections, a method of the invention can be used to express polypeptides that interfere with the maturation and/or the release of HSV particles from axons. Anterograde transport of herpes simplex virus (HSV) from the neuronal cell body to the axon terminal is crucial for the spread and transmission of the virus. An example of a polypeptide that could be useful for treating herpes simplex viral infections is a dominant-negative version of the ATPase Vps24 as Vps24 is required for herpes simplex viral envelopment (Crump et al., J. Virol. 81:7380-7387, 2007).

The viruses of the invention can be applied directly to neuronal axons at the site of injury. In some embodiments, the application or administration of the viruses of the invention may include surgical exposure of tissue that contains axons of interest or may involve injection of viral particles into an axon-rich region (e.g. stereotactic or fluoroscopic guided injection into the spinal cord). The site of administration can be a specific area, for example, an area that includes injured axons or axons that could benefit from heterologous protein expression, e.g. site of neuronal or axonal injury. The virus could be applied by injection, or in a gel foam or other excipient, for example, directly to the site where the axon is located. Alternatively, if the virus contains a coat protein that binds to axons, the virus could be delivered systemically or it could be delivered in the cerebrospinal fluid, intraperitoneally, or into another body component (e.g. in a cavity formed after injury such as those that occur after stroke). Thus, viruses of the invention can be applied by injection to a selected location, in the spinal cord for example. Viruses of the invention can also be applied topically to an injured area.

The invention also provides a method for introducing nucleic acids into the axon of a mammalian neuron. Selected nucleic acids can be packaged into virus particles as described above. The virus can be applied to a localized site, i.e. by injection or other form of application, to an area or cavity that contains axons or by application to an axon compartment of neurons grown in compartmentalized culturing device, such as Campenot chambers. The virus can also be administered systematically, for example, by intravenous injection or oral administration.

Viruses of the invention for therapeutic use can be formulated as pharmaceutical compositions for administration to a mammal such as a monkey, a rat, a mouse, a horse, a rabbit, and a human.

Pharmaceutical Compositions

The pharmaceutical compositions of the present invention comprise a therapeutically effective amount of the virus, and a pharmaceutically acceptable carrier. In a specific embodiment, the term “pharmaceutically acceptable” means approved by a regulatory agency of the Federal or a state government or listed in the U.S. Pharmacopeia or other generally recognized pharmacopeiae for use in animals, and more particularly in humans. The term “carrier” refers to a diluent, adjuvant, excipient, or vehicle with which the pharmaceutical composition is administered. Saline solutions and aqueous dextrose and glycerol solutions can also be employed as liquid carriers, particularly for injectable solutions. Suitable pharmaceutical excipients include starch, glucose, lactose, sucrose, gelatin, malt, rice, flour, chalk, silica gel, sodium stearate, glycerol monostearate, talc, sodium chloride, dried skim milk, glycerol, propylene, glycol, water, ethanol and the like. These compositions can take the form of solutions, suspensions, emulsion, tablets, pills, capsules, powders, sustained-release formulations and the like. These compositions can be formulated as a suppository. Oral formulation can include standard carriers such as pharmaceutical grades of mannitol, lactose, starch, magnesium stearate, sodium saccharine, cellulose, magnesium carbonate, etc. Examples of suitable pharmaceutical carriers are described in “Remington's Pharmaceutical Sciences” by E. W. Martin. Such compositions will contain a therapeutically effective amount of the virus, preferably in purified form, together with a suitable amount of carrier so as to provide the form for proper administration to the patient. The formulation should suit the mode of administration.

The compositions may be systemically administered, e.g., orally, in combination with a pharmaceutically acceptable vehicle such as an inert diluent. For oral administration, the virus may be combined with one or more excipients and used in the form of ingestible capsules, elixirs, suspensions, syrups, wafers, and the like. Such compositions should contain at least 0.1% of the virus. The percentage of the compositions and preparations may, of course, be varied and may conveniently be between about 2 to about 60% of the weight of a given unit dosage form. The amount of active compound in such useful compositions is such that an effective dosage level will be obtained.

The compositions may also contain the following: binders such as gum tragacanth, acacia, corn starch or gelatin; excipients such as dicalcium phosphate; a disintegrating agent such as corn starch, potato starch, alginic acid and the like; a lubricant such as magnesium stearate; and a sweetening agent such as sucrose, fructose, lactose or aspartame or a flavoring agent such as peppermint, oil of wintergreen, or cherry flavoring may be added. Various other materials may be present. For instance, a syrup or elixir may contain the virus, sucrose or fructose as a sweetening agent, methyl and propylparabens as preservatives, a dye and flavoring such as cherry or orange flavor. Of course, any material used in preparing any unit dosage form, including sustained-release preparations or devices, should be pharmaceutically acceptable and substantially non-toxic in the amounts employed.

The composition also be administered by infusion or injection to a localized site. Solutions of the virus can be prepared in water or a suitable buffer, optionally mixed with a nontoxic surfactant. Dispersions can also be prepared in glycerol, liquid polyethylene glycols, triacetin, and mixtures thereof and in oils. Under ordinary conditions of storage and use, these preparations contain a preservative to prevent the growth of undesirable microorganisms.

The pharmaceutical dosage forms suitable for injection or infusion can include sterile aqueous solutions or dispersions or sterile powders comprising the virus which are adapted for the extemporaneous preparation of sterile injectable or infusible solutions or dispersions. In all cases, the ultimate dosage form should be sterile, fluid and stable under the conditions of manufacture and storage. The liquid carrier or vehicle can be a solvent or liquid dispersion medium comprising, for example, water, ethanol, a polyol (for example, glycerol, propylene glycol, liquid polyethylene glycols, and the like), vegetable oils, nontoxic glyceryl esters, and suitable mixtures thereof. The proper fluidity can be maintained, for example, by the formation of liposomes, by the maintenance of the required particle size in the case of dispersions or by the use of surfactants. The prevention of the action of undesirable microorganisms can be brought about by various antibacterial and antifungal agents, for example, parabens, chlorobutanol, phenol, sorbic acid, thimerosal, and the like. In many cases, it will be preferable to include isotonic agents, for example, sugars, buffers or sodium chloride.

Sterile injectable solutions are prepared by incorporating the virus in the required amount in the appropriate solvent with various of the other ingredients enumerated above, as required, followed by filter sterilization.

Useful liquid carriers include water, alcohols or glycols or water-alcohol/glycol blends, in which the present viruses can be dissolved or dispersed at effective levels, optionally with the aid of non-toxic surfactants. Adjuvants such as fragrances and additional antimicrobial agents can be added to optimize the properties for a given use. The resultant liquid compositions can be applied from absorbent pads, used to impregnate bandages and other dressings, or sprayed onto the affected area using pump-type or aerosol sprayers.

Useful dosages of the viruses of the invention can be determined by comparing their in vitro activity and in vivo activity in animal models.

The administration of the composition may be for either a “prophylactic” or “therapeutic” purpose. When provided prophylactically, the compositions of the invention are provided before any symptom or clinical sign becomes manifest. The prophylactic administration of the composition serves to prevent or attenuate any subsequent symptom. When provided prophylactically, the viral compositions of the invention, are provided before any symptom or clinical sign of a disease becomes manifest. The prophylactic administration of the composition serves to prevent or attenuate one or more symptoms or clinical signs associated with the disease.

When provided therapeutically, the composition is provided upon the detection of a symptom or clinical sign of an injury or condition. The therapeutic administration of the viruses serves to attenuate further axonal degeneration or aberrant function. When provided therapeutically, a viral composition is provided upon the detection of a symptom or clinical sign of the condition or injury. The therapeutic administration of the compound(s) serves to attenuate a symptom or clinical sign of that condition or injury. Thus, a viral composition of the present invention may be provided either before the onset of the condition or injury (so as to prevent or attenuate an anticipated condition or injury) or after the onset of the condition or injury.

A composition is said to be “pharmacologically acceptable” if its administration can be tolerated by a recipient mammal. Viruses of the invention are administered in a “therapeutically effective amount” if the amount administered is physiologically significant. The amount is physiologically significant if it results in a detectable change in the physiology of a recipient patient, e.g., a decrease in aberrant axon function, an increase in axon growth or regeneration, or a decrease in axon degeneration. Thus, an “effective amount” is one that is sufficient to achieve a desired effect. It is understood that the effective dosage may be dependent upon the species, age, sex, health, and weight of the recipient, kind of concurrent treatment, if any, frequency of treatment, and the nature of the effect wanted. The ranges of effective doses provided below are not intended to limit the invention and represent dose ranges.

A composition of the invention can include one or more than one viruses of the invention and may be administered by any means that allow delivery of the viruses to the site of a neuronal axon. A composition of the invention can be administered as a single treatment, or multiple treatments, for instance, over a period up to and including between one week and about 24 months, or any range or value therein.

The invention will be further described in the following examples, which do not limit the scope of the invention described in the claims.

Examples Example 1 Intra-Axonal Translation and Retrograde Trafficking of CREB Promotes Neuronal Survival

The studies describe herein show that new growth factor (NGF) triggers axonal protein synthesis, which is required for NGF-mediated retrograde survival. A cDNA library prepared from the axons of developing sensory neurons reveals that CREB mRNA is an axonally-localized transcript. Results indicate that CREB is selectively translated in axons in response to NGF and retrogradely trafficked to the cell body. Furthermore, selective knockdown of axonal CREB mRNA reveals that axonally-synthesized CREB is required for NGF at axons to promote the accumulation of pCREB in the nucleus, transcription of a CRE-containing reporter gene, and neuronal survival. These data identify a role for axonally-synthesized CREB and identify a signaling mechanism involving intra-axonal translation and retrograde trafficking of transcription factors that may have critical roles in signaling from axons to the nucleus.

Materials & Methods

Primary Cell Culture

E15 rat or E13 mouse embryonic dorsal root ganglion (DRG) explants were plated on glass-bottom culture dishes (MatTek) or glass coverslips pre-coated with 33 μg/ml poly-D-lysine and 1 μg/ml laminin. CREB^(α/Δ −/+) animals used to generate CREB^(α/Δ −/+) embryos were from Jackson Labs. E15 dissociated DRG neurons were prepared as described by Wu et al., Nature 436, 1020-1024 (2005). DRGs were cultured in B27/Neurobasal medium (Invitrogen) supplemented with 100 ng/ml nerve growth factor (NGF) and 20 μM 5′-fluorodeoxyuridine (5-FdU) for 3 days. siRNA-mediated knockdown in DRG neurons has been described previously by Higuchi et al., Biochemical & Biophysical Research Communications 301, 804-809 (2003) and was performed using siRNAs listed in Table S3. For measurements of CREB levels in isolated axons, axons were severed from cell bodies by removing the explant with a flame-sharpened Pasteur pipette (Wu et al., Nature 436, 1020-1024 (2005)). Modified Boyden chambers were based on the procedure of Twiss (Zheng et al., Journal of Neuroscience 21, 9291-9303 (2001)) and modified to obtain distal axons as described by Wu et al., Nature 436, 1020-1024 (2005). mRNA from harvested axons (Wu et al., Nature 436, 1020-1024 (2005)) was used to prepare a cDNA library using a modified, unbiased single cell protocol as described below. See also Tietjen et al., Neuron 38, 161-175 (2003). Compartmented (Campenot) cultures were prepared as described below. See also Campenot, Proc Natl Acad Sci USA 74, 4516-4519 (1977)).

TABLE S3 siRNAs Target siRNA mRNA Sense strand sequence Source siControl Non- UAGCGACUAAACACAUCAAUU Dharmacon targeting (SEQ ID NO: 1) siCREB₆₇ CREB1 GGUUCGUCUAAUGAAGAACUU Ambion (SEQ ID NO: 2) siCREB₈₅ GGAGUCUGUGGAUAGUGUAUU Ambion (SEQ ID NO: 3)

cDNA Library Amplification

Axons were mechanically harvested, deposited directly into ice-cold PBS, and centrifuged at 2000 g for 2 min. The pellet containing purified axons was resuspended in 20 μl Lysis-RT buffer (1× MMLV buffer, 0.5% NP-40, 100 μM dNTPs, 0.1 mg/ml oligo d(T)₂₅) and incubated at 65° C. for one minute to lyse axon tissue. 100U MMLV and 1U AMV reverse transcriptases (Invitrogen) were added to the mixture and incubated at 37° C. for 15 min for first-strand cDNA synthesis. Reverse transcriptases were inactivated by incubation of the reaction mix at 65° C. for 10 min and then placed on ice. 20 μl PolyA solution (1× TdT buffer, 4 mM CoCl₂, 400 μM DTT, 200 μM dATP, 20 U TdT (Invitrogen)) was added and the solution incubated at 37° C. for 15 min for addition of an exogenous 3′ poly(A) tail to the first-strand cDNA. TdT was then inactivated by incubation of the reaction at 65° C. for 10 min, and the solution placed on ice. 8 μl of the RT/Poly(A) reaction was added to PCR Mix #1 (1× Amplitaq buffer II, 1× BSA, 2.5 mM MgCl₂, 0.05% Triton X-100, 100 μM dNTPs, 1 μM RTLib1 primer (Table S2), 5U Amplitaq (Roche)), and PCR was performed using the following conditions: 95° C. for 2 min, followed by 25 cycles of [95° C., 1 min: 42° C., 2 min: 72° C. 6 min+10 sec per cycle]. An additional 5U Amplitaq were added to the reaction and PCR was performed according to the following conditions: 95° C. for 2 min, followed by 25 cycles of [95° C., 1 min: 42° C., 2 min: 72° C. 6 min]. 2.25 μl of the reaction was then added to PCR Mix #2 (1× Amplitaq buffer II, 2.5 mM MgCl₂, 20 μM dNTPs, 5 μM RTLib2 primer (Table S2), 5 U Amplitaq) and PCR performed as follows: 95° C. for 2 min, followed by 30 cycles of [94° C., 90 sec: 42° C., 2 min: 72° C., 3 min]. Efficacy of the library was assessed by PCR using oligonucleotide primers against known axon-localized transcripts β-actin and RhoA (FIG. 3D) (Wu et al., Nature 436, 1020-1024 (2005)). Contamination by neuronal cell bodies was assessed by PCR for soma-restricted mRNAs γ-actin and histone H1f0, and contamination by glia was assessed by PCR for glial transcript GFAP.

TABLE S2 Oligonucleotide Primers Target mRNA Primer ID (gene) Sequence (5′-3′) ActinFor β-Actin CCATTGAACACGGCATTGTCACCA (SEQ ID NO: 4) ActinRev AGGGCAACATAGCACAGCTTCTCT (SEQ ID NO: 5) ATF2For ATF2 ACAAACCATGCCCGTTGCTATTCC (SEQ ID NO: 6) ATF2Rev GCTGTTTCAGCTGTGCCACTTCAT (SEQ ID NO: 7) CREBFor CREB1 TGCCACATTAGCCCAGGTATCCAT (SEQ ID NO: 8) CREBRev TGTACATCACCAGAGGCAGCTTGA (SEQ ID NO: 9) CREBFor2 TGCCACATTAGCCCAGGTATCCAT (SEQ ID NO: 10) CREBRev2 TGTTAGCCAGCTGTATTGCTCCTC (SEQ ID NO: 11) cJunFor cJun TACACAAGATGGACTGGGTTGCGA (SEQ ID NO: 12) cJunRev ACACTGGGTAGGACACCCAAACAA (SEQ ID NO: 13) Elk1For Elk1 TCTGCTGCAGCTTCTGAGAGAACA (SEQ ID NO: 14) Elk1Rev CGCATGTATTCATTCCGGCTGCTT (SEQ ID NO: 15) STAT1For STAT1 AGCTTTGAAACCCAGTTGTGCCAG (SEQ ID NO: 16) STAT1Rev TCTTCGTGTAGGGCTCAACAGCAT (SEQ ID NO: 17) RTLib1 Poly(A) + ATTGGATCCAGGCCGCTCTGGACAAA Library tag ATATGAATTC(T)₂₄ (SEQ ID NO: 18) RTLib2 ATTGGATCCAGGCCGCTCTGGACAAA ATATGAATTC (SEQ ID NO: 19)

Primary Neuronal Cultures and Compartmented Chambers

DRG neurons contained only axons and no prominent dendritic processes, as processes were prominently labeled with anti-GAP43 antibodies and did not exhibit MAP2 immunoreactivity (FIG. 1B). DRG cultures were devoid of glial contamination as determined by immunofluorescence using Schwann cell marker GalC (FIG. 1A).

Boyden Chambers were modified for axon harvest as follows: a 12 mm coverslip was placed in the centre of a 24 mm Transwell Polyester (0.3 μm pore) Chamber (Corning), and both were coated in the chamber with poly-D-lysine and laminin, as above. Six E15 DRG explants were plated on the coverslip with the aid of a cloning cylinder placed on each coverslip. At DIV5, axons from 6 separate chambers were harvested from the underside of the membrane and pooled for reverse transcription and cDNA amplification (Tietjen et al., Neuron 38, 161-175 (2003)) (see below for details), or for Western blot analysis. Protein levels were determined by the fluorescent o-phthaldialdehyde assay. Primers for detecting specific transcripts are listed in Table S2.

Campenot chambers were modified for FISH and Immunofluorescence analysis as follows: Teflon dividers were applied to poly-D-lysine, laminin and collagen (1 mg/ml)-coated Lab-Tek chambers (NUNC). The low autofluorescence of the Permanox® plastic in these chambers allows us to perform fluorescence analyses on these cultures much more readily than is possible using traditional cell culture plasticware. E15 dissociated DRG neurons were plated in the cell body compartment in media containing 100 ng/ml NGF and 20 μM 5′-fluorodeoxyuridine to inhibit glial growth. Media was changed every 2 DIV and NGF concentration in the cell body compartment was halved at each media change. At DIV 5, when axons had crossed the divide into the axonal compartment, NGF was withdrawn from the cell body compartment and experimental media containing NGF (0 ng/ml or 30 ng/ml) and/or drug treatments/siRNA transfection reagents was applied to the axon compartment for a further 2 DIV. All media were completely replaced every subsequent 12 hours to ensure purity of the conditions in the respective compartments. Neurons that projected axons across the divide into the axon compartment were retrogradely labeled by addition of Alexa555-conjugated wheat germ agglutinin (WGA) (2 μg/ml, Molecular Probes) to the axon compartment 1 hour before the end of the experiment. Fluidic isolation and the absence of contamination of the chambers were assessed by a number of strict criteria, failure to meet any of which resulted in the culture being discarded from analysis.

Compartments were regularly checked for water-tightness during the frequent media changes. Bulk leakage between compartments is readily visible and excludes cultures from further study. Phenol red was selectively added to compartments, and media from opposing compartments were checked for phenol red exclusion by measuring absorption at 560 nm following subsequent media changes. Detectable presence of phenol red in untreated compartments excluded the culture from analysis.

Batches of compartments were regularly screened by immunofluorescence for Schwann cell marker GalC (FIG. 1A). Our culture media are optimized to prevent glial growth (Wu et al., Nature 436, 1020-1024 (2005)), and the presence of any Schwann cells in screened cultures resulted in discarding the entire batch.

Cultures were routinely counter-stained with DAPI during immunofluorescence and TUNEL assays. The presence of a single DAPI-stained nucleus in the axon compartment or within the divider area was sufficient to reject the culture from analysis.

Axons crossing into the axon compartment were retrogradely labeled with WGA-Alexa555, as above. Cultures were checked to ensure that background Alexa555 staining of the substratum was contained in the axon compartment, with no diffusion across the divider. Presence of background Alexa555 staining outside of the discrete border of the axon compartment excluded the culture from analysis.

Axons crossing the divider were analyzed: as in FIG. 1B, axons fasciculate to form single, discrete bundles that cross the divider. Axon populations that fail to fasciculate into a single pathway for >300 μm were rejected from analysis, due to inference of an incomplete barrier between the compartments.

Only WGA-Alexa555-labeled cell bodies are included in the data set. For cell body immunofluorescence measurements, regions of interest (ROI) are defined by the perimeter outline of each WGA-positive cell body. ROIs were transposed to respective immunofluorescence micrographs for analysis of cell body fluorescence levels. FIG. 1C, 10C demonstrate that some cell bodies in the cell body compartment are not WGA-labeled (i.e. fail to extend axons across the divider), and are thus not relevant to the data set. These cells are therefore not used to generate ROIs for fluorescence analysis.

Cultures were fixed at 7 DIV using 4% formaldehyde for 20 min at 25° C., followed by TUNEL assay staining, as per manufacturer's protocol (ApoAlert, Clontech) or in situ hybridization or immunofluorescence, as described below.

In situ Hybridization

Sense oligonucleotides (Table S1) were synthesized with a T7 promoter site at their 3′ end. Antisense riboprobes were in vitro transcribed from the sense oligonucleotides using the MEGAscript T7 transcription kit (Ambion) with digoxigenin-conjugated UTP. DRGs (DIV3) were fixed overnight at 4° C. in 4% paraformaldehyde in cytoskeleton buffer (CSB: 10 mM MES pH 6.1, 138 mM KCl, 3 mM MgCl2, 2 mM EGTA, 0.4 M sucrose). Washes were performed in TBST (20 mM Tris pH 8.0, 150 mM NaCl, 0.1% Triton X-100) for 3×5 min. DRGs were permeabilized in 0.5% Triton X-100/TBS for 10 min and post-fixed in 4% PFA/TBS for 5 min, followed by fresh acetylation buffer (0.25% acetic anhydride, 0.1 M HEPES) for 10 min, and equilibration with 4×SSC/50% formamide for 30 min. Cultures were incubated with 15 ng riboprobes (Table S1) in 15 μl hybridization buffer (10% dextran sulfate, 4×SSC, 1× Denhardt's Solution, 40% formamide, 20 mM ribonucleoside vanadyl complex, 10 mM DTT, 1 mg/ml yeast tRNA, and 1 mg/ml salmon sperm DNA) at 37° C. overnight. The coverslips were washed with 40% formamide/1×SSC at 37° C. for 20 min, and three times each with 1×SSC and 0.1×SSC at RT for 5 min. Neurons were blocked with blocking buffer (100 mM Tris-HCl pH 8.0, 150 mM NaCl, 8% formamide, 5% BSA, 2.5% normal horse serum, and 2.5% normal goat serum) for 30 min. Hybridization was detected with anti-digoxin antibody (Table S4), which was precleared with rat embryo power in blocking buffer for 2 h at 25° C. Mean fluorescence intensity elicited by the scrambled probe was subsequently deducted from all FISH data to produce specific labeling intensity for each probe.

TABLE S1 In Situ Riboprobe Template Oligonucleotides Target Oligo. ID mRNA Target Sequence (5′-3′) Scrambled Non- TGTACGTCTCGCCTTGCAACTCGTAC targeting TGTGAGGTAGTCGCGCGACAGTGC (SEQ ID NO: 20) HistoneH1FISH Histone GTACCTGACGGCCGAAATCCTGGAG H1f0 CTTGCGGCTAATGCGGCGAGGGACA (SEQ ID NO: 21) CREBFISH CREB1 CTCAGCCGGGTACTACCATTCTACAA TATGCACAGACCACTGATGGACAG (SEQ ID NO: 22) CREBFISH2 CGGCCCAGCCATCAGTTATTCAGTCT CCACAAGTCCAAACAGTTCAGTCT (SEQ ID NO: 23) CREBSense CREB1 CTGTCCATCAGTGGTCTGTGCATATT (Sense GTAGAATGGTAGTACCCGGCTGAG strand) (SEQ ID NO: 24) CREB2Sense AGACTGAACTGTTTGGACTTGTGGA GACTGAATAACTGATGGCTGGGCCG (SEQ ID NO: 25) cJunFISH cJun GACTGTAGATTGCTTCTCTAGTGCTC CGTAAGAACACAAAGCAGGGAGGG (SEQ ID NO: 26) STAT1FISH STAT1 CCCTAATGCTGGCCCTGATGGTCTTA TTCCATGGACAAGGTTCTGTAAGG (SEQ ID NO: 27) ActinFISH β-Actin GTATGCCTCTGGTCGTACCACTGGCA TTGTGATGGACTCCGGAGACGGG (SEQ ID NO: 28)

Quantification of CREB Protein Levels

Images and measurements of signals in axons were taken from the terminal 50 μm of the axon, except where indicated. Analyzed axons were a minimum of 2000 μm for all experiments. DRGs were fixed with 4% PFA in CBS overnight at 4° C., permeabilized with 0.5% Triton X-100/TBS, and blocked in 4% BSA/TBS for 1 hour. DRGs were labeled with antibodies (Table S4) in 2% BSA/0.1% Triton X-100/TBS overnight at 4° C. For image acquisition details, see below.

TABLE S4 Primary Antibodies Dilution Target Dilution (Western Antibody Protein (IF/FISH) blot) Source CST-9452 4E-BP1 1:250 — Cell Signaling sc-12884 p-4E-BP1 1:200 — Santa Cruz CST-9192 CREB1 1:250 1:1000 Cell Signaling sc-186 CREB1 1:250 1:250 Santa Cruz CST-9191 ^(s133)pCREB1 1:250 1:1000 Cell Signaling sc-7978 ^(s133)pCREB1 1:250 1:250 Santa Cruz 1333062 Digoxigenin 1:500 — Roche sc-16564 pErk5 1:100 — Santa Cruz CST-2212 Ribosomal S6 1:500 — Cell Signaling AB5819 Staufen 1:500 — Chemicon ab14734 VDAC/Porin-1 1:2000 — AbCam sc-12885 phospho-eIF4E 1:250 — Santa Cruz MAB3420 Tau 1:500 1:1000 Chemicon AB5220 GAP43 1:2000 — Chemicon MAB378 MAP2 1:500 — Chemicon sc-118 TrkA 1:250 — Santa Cruz CST-9141 pTrkA 1:250 — Cell Signaling G745A Luciferase 1:50 1:1000 Promega

Image Acquisition and Data Handling

Optimal exposure times for both mRNAs (in situ hybridization) and immunofluorescence (IF), were determined empirically for each riboprobe/antibody and kept constant and below grey scale saturation. Cell body FISH, TUNEL and IF signals were obtained using a 20× objective, while axonal FISH and IF signals were acquired using a 60× objective. Image acquisition was kept within the linear range of the camera by maintaining maximum fluorescence signals below 50% saturation of the photodetector CCD chip. Immunofluorescence and FISH images were taken with a Nikon Eclipse TE2000-U inverted microscope with a CoolSnap HQ CCD camera. Image stacks were deconvoluted using AutoDeblur v9.3 (AutoQuant). The volumes of individual axons were calculated from GAP43 or WGA counterstains using Metamorph v6.2r1 following 3D deconvolution with AutoDeblur v9.3. Specific fluorescence signals from axons were then normalised to the calculated axon volume and are presented as normalised fluorescence intensities per pixel. Within each experiment, exposure times were kept constant throughout and all data were analysed and images processed using Metamorph v6.2r1 software (Universal Imaging). Dendra fluorescence levels were acquired using an Inverted Olympus IX-70 DeltaVision Image Restoration microscope with a 40× objective and acquired by a CoolSnap QE camera (Photometrics). Photoactivation of Dendra was achieved by a 50 ms illumination (for selected growth cones) or 1 s illumination (for cell body Dendra accumulation analysis in low density dissociated DRG cultures) with a 408 nm laser light source. For all microscopy experiments, sample identities were blindly encoded prior to image acquisition and analysis. Identities of the experimental samples were then revealed after imaging and data analysis.

All statistical p values in this study were determined using ANOVA from experiments repeated a minimum of three times, unless stated otherwise. All data are presented as mean +/− s.e.m. n values are represented on all graphs and defined in legends, unless stated otherwise.

Generation and Infection of Recombinant Viruses

The vectors used were a modified Sindbis vector, pSinRep5, containing a point mutation in nsP2 (P726S) that reduces cytotoxicity in neurons (Jeromin et al., Journal of Neurophysiology 90, 2741-2745 (2003)) and the helper plasmid DH-BB (S. Schlesinger, Washington University, St. Louis) as described by Wu et al., Nature 436, 1020-1024 (2005). Reporter experiments utilized the myr-dEGFP system (Aakalu et al, Neuron 30, 489-502 (2001)), except that a d1EGFP variant (i.e., an EGFP with a 1 hour half-life) was used, as described by Wu et al., Nature 436, 1020-1024 (2005). pSinRep5-myr-dEGFP_(3′CREB) and pSinRep5-myr-dEGFP_(3′RhoA) contained the full-length 3′UTR of the human CREB mRNA or the 3′UTR of human RhoA mRNA, fused to the viral 3′CSE. For Sindbis virus encoding Dendra constructs, the virus contained the open reading frame (ORF) of Dendra and, in the case of pSinRep5-Dendra-CREB, the full ORF of human CREB, followed by a 54 nt minimal axonal targeting element (Kislauskis et al., Journal of Cell Biology 127, 441-451 (1994)). In the case of IRES-driven Sindbis virus, the pSinRep constructs contained a human encephalomyocarditis viral IRES element from vector pIRES-hyg (BD Biosciences). Sindbis pseudoviruses were prepared according to the manufacturer's instructions (Invitrogen), purified on a sucrose gradient, concentrated on YM-100 microcon columns, resuspended in Neurobasal medium, and titered using BHK-21 cells. We generated a CRE-luciferase adenovirus reporter by subcloning the complete CRE-Luc reporter gene from vector pCRE-Luc (BD Biosciences) into pAd/PL-DEST (Invitrogen). Virus production and amplification was performed in HEK293A cells, according to manufacturer's instructions. Adenovirus was purified using the ViraKit AdenoMini-4 system (Virapur), and titered using HEK293T cells. DRGs were infected with equal infectious units of recombinant virus at DIVE and luciferase levels were measured 24 hour later.

Results

Retrograde NGF Signalling at Axon Terminals Requires Protein Synthesis

To determine if NGF might regulate local protein synthesis, embryonic day 15 (E15) dorsal root ganglia (DRG) cultures (FIG. 1A, 1B) were transferred to NGF-free media for 2 hour and then stimulated with NGF or vehicle for 1 hour. NGF treatment resulted in increased phosphorylation of 4E-BP1 at S64 and T69 in axons (FIG. 2A, 1B). Multisite phosphorylation of 4E-BP1 is required for mRNA translation (Richter & Sonenberg, Nature 433, 477-480 (2005)), indicating that NGF may induce local protein synthesis.

To determine if protein synthesis is required for NGF signaling we cultured neurons in compartmented chambers, which permit selective application of NGF to either distal axons or cell bodies (Campenot, Proc Natl Acad Sci USA 74, 4516-4519 (1977)), mimicking the physiologically selective exposure of distal axons to NGF that occurs as axons approach NGF-synthesizing target tissues (FIG. 2C, FIG. 1C-1F). Axonal application of NGF activates a survival pathway that utilizes CREB, resembling the physiologic requirement for CREB (Lonze et al., Neuron 34, 371-385 (2002)); bath application appears to utilize different NGF signaling pathways, as it induces survival in the absence of CREB (Lonze et al., Neuron 34, 371-385 (2002)). Axons crossed the divider by DIV 5, at which point the media in the cell body compartment was replaced with NGF-free media and the media in the axonal compartment is replaced with either NGF-free or NGF-replete media for an additional 48 hour. Application of NGF exclusively to the axonal compartment resulted in a significant increase in neuronal survival compared to vehicle-treated axons (FIG. 2D, 2E). This effect required intra-axonal protein synthesis, as axonal application of cycloheximide or anisomycin, together with NGF, resulted in a significant reduction in survival compared to NGF alone (FIG. 2D, 2E). The fluidic isolation of treatments was confirmed by our finding that axonal application of translation inhibitors had no effect in the cell body compartment on a membrane-anchored translation reporter (FIG. 1E, 1F). Furthermore, incubation of translation inhibitors in the cell body compartment supported DRG survival, even in the absence of NGF (FIG. 2E), consistent with previous results that have shown that protein synthesis inhibition in various cells, including DRG neurons, promotes survival due to the requirement for new protein synthesis in apoptotis (Tong et al., J Neurocytol 26, 771-777 (1997), Martin et al., J Cell Biol 106, 829-844 (1988), Wyllie et al., Journal of Pathology 142, 67-77 (1984)).

CREB mRNA is Localized to Axons

To identify mRNAs that act downstream of NGF in axons, the Boyden chamber technique for isolating axons (Zheng et al., Journal of Neuroscience 21, 9291-9303 (2001)) was modified in order to obtain distal axons (FIG. 3A) (Wu et al., Nature 436, 1020-1024 (2005)). DRG explants were cultured on 12-mm coverslips placed in the centre of Boyden chambers. Axons grow across the coverslip and then grow through the membrane towards the higher NGF concentration in the lower chamber. Axons from six chambers were harvested by scraping the underside of the membrane and used for reverse transcription and cDNA amplification using a protocol designed for unbiased amplification of mRNA from single cells (Tietjen et al., Neuron 38, 161-175 (2003)) (See Materials & Methods).

Among the clones in the library, cDNAs encoding specific transcription factors, including CREB were identified. To confirm that CREB transcripts were localized to axons, we performed fluorescent in situ hybridization (FISH) experiments using E15 DRG explant cultures. CREB-specific riboprobes prominently labeled cell bodies (FIG. 3B), with lower levels detectable in axons (FIG. 3B, 3C). Probes directed against other transcription factor transcripts, such as cJun and STAT1, resulted in negligible labeling of axons (FIG. 3B, 3C). CREB FISH signals were markedly reduced in neurons transfected with CREB-specific siRNA (FIG. 3D, 3E), as well as in DRG neurons cultured from mice homozygous for a hypomorphic CREB allele (Blendy et al., EMBO Journal 15, 1098-1106 (1996)) (FIG. 1G, 1H). RT-PCR using two distinct primer pairs resulted in amplification of CREB transcripts from distal axon preparations from Boyden chambers (Wu et al., Nature 436, 1020-1024 (2005)), as well as amplification of β-actin, a previously-identified axonal mRNA (Olink-Coux & Hollenbeck, Journal of Neuroscience 16, 1346-1358 (1996)), while RT-PCR signals for other transcription factor transcripts were absent (FIG. 3F). The axonal localization of CREB mRNA is consistent with the localization of CREB mRNA and protein to dendrites (Crino et al., Proceedings of the National Academy of Sciences of the United States of America 95, 2313-2318 (1998)). Together, these data indicate that CREB transcripts are specifically localized to axons of developing DRG neurons.

CREB is Synthesized in Axon Terminals in Response to NGF

The presence of axonal CREB mRNA raises the possibility of intra-axonal CREB synthesis. To address this, DRG explants were cultured in Boyden chambers; the media in the cell body chamber was replaced with NGF-free media and the media in the axon chamber was replaced with either NGF-replete or NGF-free media for 3 hours. Extracts from the upper surface of the Boyden chamber, containing cell bodies and proximal axons, and the lower surface, containing exclusively distal axons (Wu et al., Nature 436, 1020-1024 (2005)), were harvested, and equal amounts of protein were analyzed by Western blot. Western blotting using a CREB family antibody that also recognizes CREM and ATF1 indicated that only CREB was present in distal axons and was dependent on the presence of NGF in the axon compartment (FIG. 4A, FIG. 1I), although all three proteins were detected in the cell body/proximal axon fraction (FIG. 4A).

The axonal localization of CREB was also examined by immunofluorescence. Axons were severed from cultured DRG explants to rule out potential contributions from anterograde transport of cell body-derived CREB. Immunofluorescence with a CREB-specific antibody revealed axonal CREB protein was present when the media contained NGF, but not when the media was exchanged with NGF-free media for 3 hour (FIG. 4B, 4C), consistent with the Western blot data. Although the majority of CREB protein localized to the nucleus, with substantially lower levels in axons (FIG. 4D), the immunofluorescence signal in axons was specific. Similar immunofluorescence staining was seen using a different CREB-specific antibody that recognized a non-overlapping epitope. In addition, immunofluorescence staining was substantially reduced in DRG neurons transfected with CREB-specific siRNA and in DRG neurons prepared from mouse embryos homozygous for a hypomorphic CREB allele (Blendy et al., EMBO Journal 15, 1098-1106 (1996)) (FIG. 1J-1O). The presence of CREB in severed axons was dependent upon NGF and local translation since replacement of the media with NGF-free media or NGF-replete media containing cycloheximide resulted in a loss of CREB immunoreactivity (FIG. 4B, 4C). These data indicate that CREB is found in axons and its levels are dependent on NGF.

CREB mRNA is Selectively Translated in Response to NGF

NGF-dependent axonal CREB translation was examined using a GFP-based reporter assay (Aakalu et al., Neuron 30, 489-502 (2001)). This reporter expresses a transcript encoding a destabilized enhanced GFP with a cellular half-life of 1 hour (dEGFP) that enables dynamic changes in translational activity to be reflected by changes in fluorescence intensity (Aakalu et al., Neuron 30, 489-502 (2001)). The dEGFP construct also contains a myristoylation sequence, resulting in reduced diffusion of the reporter in the membrane (Wu et al., Nature 436, 1020-1024 (2005), Aakalu et al., Neuron 30, 489-502 (2001)). As a result of these two features, fluorescence signals reflect newly-synthesized protein near the site of translation as evidenced by their proximity to ribosomes (Aakalu et al., Neuron 30, 489-502 (2001)).

DRG explant cultures were infected with Sindbis virus (Wu et al., Nature 436, 1020-1024 (2005), Jeromin et al., Journal of Neurophysiology 90, 2741-2745 (2003)) expressing an mRNA comprising the myr-dEGFP coding sequence and the 3′UTR of CREB (myr-dEGFP_(3′CREB)) (FIG. 5A). Infection resulted in the appearance of fluorescent puncta throughout infected axons (FIG. 5B), as has previously been found in cultures infected with myr-dEGFP_(3′RhoA) (Wu et al., Nature 436, 1020-1024 (2005)). No fluorescent signals are detected in axons of DRGs infected with a histone H1f0 myr-dEGFP reporter, an mRNA that is not detectable in axons (FIG. 6A, 6B). Fluorescent myr-dEGFP_(3′CREB) puncta disappeared following replacement of the media with NGF-free media and reappeared following restoration of NGF, but not Semaphorin 3A (Sema3A), an axonal guidance cue that regulates the translation of axonal RhoA mRNA (FIG. 5B) (Wu et al., Nature 436, 1020-1024 (2005)). Expressing the RhoA reporter myr-dEGFP_(3′RhoA) led to fluorescent puncta throughout axons that were only slightly affected by removal of NGF (FIG. 6B). These observations indicate that the CREB reporter is responsive to NGF but not to Sema3A, suggesting that the CREB 3′UTR contains a NGF-response element and that axons contain distinct signaling pathways that regulate the translation of different mRNA transcripts. The punctuate myr-dEGFP signals may reflect “hotspots” of protein translation (Aakalu et al., Neuron 30, 489-502 (2001), as these puncta co-localized with ribosomal protein S6, phospho-eIF4E, and Staufen, but not mitochondria (FIG. 5C, FIG. 6C, 6D).

Locally Synthesized CREB is Retrogradely Trafficked to the Nucleus

The importin proteins, which bind nuclear-localization sequences (NLS) (Goldfarb et al., Trends in Cell Biology 14, 505-514 (2004)), are present in axons and mediate the retrograde trafficking of axonally-injected fluorescently-labeled NLS peptides (Hanz et al., Neuron 40, 1095-1104 (2003)). Since CREB contains a NLS that mediates its nuclear localization (Waeber & Habener, Mol Endocrinol 5, 1418-1430 (1991)), axonal CREB may be retrogradely transported to the cell body. To determine if endogenously-expressed CREB is retrogradely trafficked, we examined the time course of CREB reduction in axons upon replacement of media with NGF-free media. CREB levels decreased to baseline within 3 hours of NGF removal, and returned to original levels 2 hours following restoration of NGF, although significant recovery in CREB levels (˜40%) was observed within 30 min of NGF restoration (FIG. 7A). These treatments did not affect GAP-43 (FIG. 7A) or axonal CREB mRNA levels (FIG. 6E). The NGF-dependent restoration of CREB levels was abolished by ribosomal inhibitors (FIG. 7A). The reduction of CREB levels upon removal of NGF was unaffected by the presence of the proteasome inhibitor LLnL (FIG. 7B, FIG. 6F), indicating a proteasome-independent pathway for CREB removal from axons. Application of colchicine, which prevents microtubule-dependent transport, abolished the reduction in CREB levels following removal of NGF (FIG. 7B), indicating a microtubule-dependent process for the loss of CREB protein from axons. The possibility of retrograde transport is supported by the finding that the loss of CREB protein occurs first in distal axons, and then subsequently in medial and proximal axon segments (FIG. 6G).

To further examine retrograde trafficking of CREB, Dendra, a monomeric GFP relative that converts from green to red fluorescence upon irradiation with blue or ultraviolet light (Kislauskis et al., Journal of Cell Biology 127, 441-451 (1994)) was used. DRG explant cultures were infected with Sindbis virus encoding either Dendra or Dendra-CREB transcripts that contained a minimal 3′UTR axon-targeting element (Kislauskis et al., Journal of Cell Biology 127, 441-451 (1994), Zhang et al., Neuron 31, 261-275 (2001)). Dendra and Dendra-CREB were photoconverted in selected growth cones (FIG. 8A). The rate of Dendra movement towards the cell body matched the rate predicted by passive diffusion (FIG. 8B). In contrast, photoconverted Dendra-CREB was observed to move at a substantially higher, and constant, rate towards the cell body of 7.8-8.8 mm h-1 (FIG. 8A, 8B), similar to previously measured rates of retrograde trafficking (Brimijoin & Helland, Brain Research 102, 217-228 (1976), Ure et al., Journal of Neuroscience 17, 1282-1290 (1997)). Retrograde transport was significantly blocked by colchicine or ethacrynic acid, a dynein inhibitor (Martenson et al., Toxicol Appl Pharmacol 133, 73-81 (1995)), suggesting a microtubule motor-dependent active transport of Dendra-CREB from the axon (FIG. 8B). Photoconversion of a 40-μm section of axon approximately 1000 μm from the cell body was associated with accumulation of photoconverted Dendra-CREB, but not Dendra, in the nucleus within 20 min (FIG. 8C, 8D).

TrkA-containing signaling endosomes are trafficked from distal axons to the cell body (Zweifel et al., Nature Reviews Neuroscience 6, 615-625 (2005)) and mediate the activation of Erk5, which is required for CREB phosphorylation in response to axonally-applied NGF (Watson et al., Nature Neuroscience 4, 981-988 (2001)). Punctate regions of phospho-TrkA (pTrkA) immunoreactivity were found along the length of axons of DRG neurons cultured in the presence of NGF (FIG. 6H), in a distribution consistent with previous reports of TrkA-signaling endosomes in axons (Cui et al., Proc Natl Acad Sci USA 104, 13666-13671 (2007). These regions of pTrkA reactivity also contain phosphorylated Erk5 (FIG. 6H). Interestingly, axonal CREB protein exhibits co-localization with these sites of pTrkA immunoreactivity along axons (FIG. 6H), indicating that axonal CREB may be in proximity to TrkA-signaling complexes in axons.

Axonal CREB is Required for the Accumulation of pCREB in the Nucleus Induced by Application of NGF to Axons

To determine whether the amounts of CREB synthesized in axons make a substantial contribution to nuclear levels of CREB, the following study was performed. Axonal CREB mRNA was knocked down by compartmentalized siRNA transfection (Hengst et al., J Neurosci 26, 5727-5732 (2006)), while BOC-Asp(OMe)-FMK (BAF), a caspase inhibitor, was included in the cell body compartment to prevent neuronal death (Kuruvilla et al., Cell 118, 243-255 (2004)). Transfection of CREB-specific siRNA into the axon compartment of dissociated DRG neurons in compartmented chambers resulted in axonal knockdown of CREB protein (72.8+/−5.2%) and CREB mRNA (82.5+/−4.3%), but did not lead to a reduction in CREB mRNA or protein levels in the cell body compartment (FIG. 9A, 9B, FIG. 10A, 10B). Similarly, selective reductions in axonal CREB protein levels are seen by Western blotting (FIG. 10C). These effects are specific, as β-actin mRNA levels in axons or cell bodies were not affected by axonal transfection of CREB-specific siRNA (FIG. 10B).

Unlike CREB, which is readily detected in the nucleus, Ser133-phosphorylated CREB (pCREB) is present at negligible levels in the nuclei of unstimulated sensory neurons (Riccio et al., Science 277, 1097-1100 (1997), Watson et al., J Neurosci. 19, 7889-7900 (1999)). The low basal level of pCREB makes neurons highly responsive to increases in pCREB levels, which occurs upon application of neurotrophin to axons (Watson et al., J Neurosci. 19, 7889-7900 (1999)) (FIG. 9C, FIG. 10D). Treatment of axons with NGF resulted in increased levels of pCREB in the nucleus within 20 min, which was unaffected by axonal transfection of a control siRNA. Axonal transfection of CREB-specific siRNA significantly reduced the ability of axonally-applied NGF to induce this rapid increase in nuclear pCREB levels (FIG. 9C, FIG. 10D), but did not have a significant effect on cell body accumulation of pTrkA or pERK5 (FIG. 10E, 10F), suggesting that this effect is not due to inhibition of retrograde transport of signaling endosomes. Knockdown of axonal CREB mRNA also did not affect nuclear pCREB accumulation induced by stimulation of cell bodies with NGF (FIG. 9C), demonstrating that axon-specific CREB knockdown does not have a general inhibitory effect on NGF signaling or CREB phosphorylation. The appearance of pCREB in the nucleus within 20 min of NGF treatment is consistent with the time required for CREB to be transported across the 1-mm divider, based on the trafficking rates measured for Dendra-CREB (FIG. 8B). Thus, while axonal synthesis does not contribute a substantial portion to the total amount of nuclear CREB, these data indicate that the axonally-synthesized pool of CREB accounts for the majority of the pCREB that appears in the nucleus upon stimulation of distal axons with NGF.

Axonal CREB Mediates the Induction of CRE-dependent Transcription

To determine whether axon-derived CREB is capable of affecting CRE-dependent transcription, axons of dissociated DRG neurons in compartmented chambers were subjected to either NGF-replete or NGF-free media and siRNA at 5 DIV. BAF was included in the cell body compartment to prevent neuronal death. At 6 DIV, cell bodies were infected with adenovirus encoding a CRE-luciferase reporter, and cellular luciferase levels were measured 24 hours later. Bath application of NGF to DRG neurons lead to a dose-dependent increase in luciferase immunofluorescence, but did not affect a control protein (FIG. 10G). Axonal application of NGF increased luciferase levels, which was prevented by axon-specific transfection of CREB-specific siRNA, but not control siRNA (FIG. 9D). Knockdown of axonal CREB mRNA did not affect luciferase transcription induced by NGF applied to the cell bodies (FIG. 9D) indicating that axonal CREB knockdown does not non-specifically inhibit the reporter. Axon-derived CREB is thus necessary for CRE-dependent transcription induced by application of NGF to distal axons.

Axonal CREB is Required for NGF-Induced Retrograde Survival

A role for CREB in DRG neuron survival is reflected in the loss of ˜75% of these neurons in CREB null mice (Lonze et al., Neuron 34, 371-385 (2002)). To determine the role of the axonal CREB in neuronal survival, DRG neurons were cultured in compartmented chambers, and axons were transfected with either control or CREB-specific siRNA. Neuronal survival induced by axonal application of NGF was unaffected by control siRNA, but was markedly impaired by transfection with either of two CREB-specific siRNAs (FIG. 9E). Axon-specific transfection of CREB-specific siRNA did not affect cell survival elicited by application of NGF to cell bodies (FIG. 9E) indicating that NGF signaling at cell bodies does not require axonal CREB. The impairment in survival seen following knockdown of axonal CREB mRNA was comparable to that seen when CREB mRNA was knocked down throughout both cell bodies and axons by transfection of cell bodies with CREB-specific siRNA (FIG. 9E) and similar to the levels of survival seen when both cell bodies and axons are deprived of NGF (FIG. 2E, FIG. 1D) (Watson et al., Nature Neuroscience 4, 981-988 (2001)). These data indicate that axonal CREB translation is required for survival elicited by NGF signaling in distal axons.

These studies reveal a role for intra-axonal mRNA translation in mediating communication between distal axons and the nucleus. CREB mRNA is localized to axons of DRG neurons and translated in response to NGF signaling. Axon-derived CREB is the source of the pCREB that appears in the nucleus following exposure of distal axons to NGF, and is required for the increase in CRE-dependent transcription seen upon stimulation of distal axons with NGF. Furthermore, neuronal survival elicited by NGF signaling at distal axons requires axon-derived CREB. These data indicate that the retrograde signal generated upon axonal application of NGF includes axonally synthesized CREB (FIG. 11). These findings identify a novel function for local translation involving the translation and retrograde trafficking of transcription factors from the axon to the neuronal nucleus. The regulation of local protein synthesis within axons adds to the previously described signaling pathways downstream of NGF/TrkA. NGF signaling is selective as it leads to the induction of the CREB mRNA translational reporter, but not the RhoA reporter, which is regulated by Sema3A4. This selectivity suggests the presence of sequence elements in the CREB 3′UTR that specifically confer NGF-responsiveness.

A common feature of many types of growth factor signaling pathways, including NGF signaling, is the occurrence of intracellular “signaling platforms” that function as localized signal transduction units (Hoeller et al., Curr Opin Cell Biol 17, 107-111 (2005)). NGF-mediated TrkA signaling can occur through TrkA at the plasma membrane as well as TrkA localized to endosomes that form upon internalization of NGF/TrkA complexes (Howe et al., Neuron 32, 801-814 (2001), Delcroix et al., Neuron 39, 69-84 (2003)). These distinct platforms are characterized by unique cohorts of proximally localized TrkA effectors (Howe et al., Neuron 32, 801-814 (2001), Delcroix et al., Neuron 39, 69-84 (2003)). Retrograde trafficking of TrkA signaling endosomes, containing both catalytically-active TrkA as well as specific TrkA effectors, is associated with an increase in pCREB levels in the nucleus in a Mek5 and Erk5-dependent pathway (Watson et al., Nature Neuroscience 4, 981-988 (2001)). However, whether CREB is similarly compartmentalized into an effector pool that is preferentially regulated by the signaling endosome has not previously been addressed. We find that CREB is found colocalized with pTrkA in axons: since both CREB and TrkA-signaling endosomes are retrogradely trafficked, the proximity of the pool of axonally-derived CREB may make it preferentially accessible to phosphorylation by TrkA effectors such as Erk5 (Watson et al., Nature Neuroscience 4, 981-988 (2001)). As TrkA kinase activity in the cell body is required for CREB phosphorylation (Riccio et al., Science 277, 1097-1100 (1997)), several models could explain how CREB phosphorylation is regulated: (1) CREB is not phosphorylated until it arrives in the cell body; (2) CREB is readily dephosphorylated, and TrkA activity is required to maintain CREB in a phosphorylated state when it arrives in the cell body; or (3) TrkA activity is required to inactivate a cell body phosphatase.

Transcriptional effects elicited by axonal signaling require that an axon-derived signal be conveyed to the cell body. An inherent requirement in this type of signaling is that the axon-derived signal must somehow be distinguished from what would presumably be a much larger amount of similar molecules in the cell body. The low basal level of pCREB in the nucleus of unstimulated neurons (Watson et al., Nature Neuroscience 4, 981-988 (2001)) may allow small increases in the amount of pCREB derived from the axon to result in a substantial fold elevation in pCREB-dependent transcriptional activity. These results indicate that axonally-synthesized CREB is capable of exerting transcriptional effects in the nucleus by serving as the source of the pCREB that appears in the nucleus following axonal application of NGF. Because the transcriptional effects of CREB are affected by its phosphorylation at sites other than Ser133 (Kornhauser et al., Neuron 34, 221-233 (2002); Johannessen et al., Cell Signal 16, 1211-1227 (2004)) as well as by protein-protein interactions (Johannessen et al., Cell Signal 16, 1211-1227 (2004)), axon-specific CREB modifications may also impart axonally-synthesized CREB with unique transcriptional effects that differ from cell body-localized CREB.

Several examples of transcription factors or transcriptional regulators localized to dendrites, and less frequently, developing axons have been described; these include CREB (Crino et al., Proceedings of the National Academy of Sciences of the United States of America 95, 2313-2318 (1998)) and NF-κB (Meffert et al., Nature Neuroscience 6, 1072-1078 (2003) in dendrites, and nervy in axons (Terman & Kolodkin, Science 303, 1204-1207 (2004)). These transcription factors may have non-nuclear functions; for example, in axons, nervy acts as an adapter protein for signaling from Plexin receptors (Terman & Kolodkin, Science 303, 1204-1207 (2004)). In the case of dendritic NF-κB, a role for transcriptional regulation has been proposed (Meffert et al., Nature Neuroscience 6, 1072-1078 (2003); however, these studies have not been able to differentiate the role of the somatic and dendritic pool of NF-κB. Similarly, while it is clear that CREB can be synthesized in dendrites (Crino et al., Proceedings of the National Academy of Sciences of the United States of America 95, 2313-2318 (1998)), the inherent difficulties in selectively abolishing the dendritic CREB pool have prevented a thorough elucidation of the exact role of dendritically-synthesized CREB in neuronal signaling. By selectively abolishing axonal CREB mRNA, the data presented here supports a nuclear role for extrasomatic pools of CREB.

During development, axons encounter a variety of signals that affect multiple aspects of neuronal development, such as axonal elongation, branching, and pathfinding, as well as synaptogenesis and neuronal differentiation (Hodge et al., Neuron 55, 572-586 (2007), Allan et al., Cell 113, 73-86 (2003), Marques et al., Development 130, 5457-5470 (2003)). Increasing evidence suggests that many of these processes involve retrograde signals that affect gene transcription. Translation and retrograde trafficking of axonally-localized transcription factor mRNAs in response to target derived signaling molecules could therefore constitute a general mechanism by which signaling at growth cones can selectively and temporally regulate gene transcription during neuronal development.

In sum, these studies show that axons of developing mammalian neurons contain mRNA encoding the cAMP-responsive element (CRE)-binding protein (CREB). CREB is translated within axons in response to new growth factor (NGF) and is retrogradely trafficked to the cell body. In neurons that are selectively deficient in axonal CREB transcripts, increases in nuclear pCREB, CRE-mediated transcription, and neuronal survival elicited by axonal application of NGF are abolished, indicating a signaling function for axonally synthesized CREB. These studies identify a signaling role for axonally-derived CREB, and indicate that signal-dependent synthesis and retrograde trafficking of transcription factors enables specific transcriptional responses to signaling events at distal axons.

Example 2 Viral-Mediated Protein Expression in Axons

It is unclear whether protein translation occurs in the axons of the mature nervous. The synthetic capacity of the axon is considered to be low and may be insufficient to make meaningful or detectable quantitites of proteins. Furthermore, direct introduction of RNA into an axon is considered unlikely to be able to be translated since current thinking suggests that RNAs that are meant to be translated in axons are prepackaged into RNA granules bound to ribosomes in the cell body. The translational capacity of axons is thought to be very different from the cell body due to the absence of standard protein translational machinery such as golgi or endoplasmic reticulum. Other aspects of the translational capacity of axons, such as the ability to utilize an IRES sequence, are unknown. Therefore, current thinking is not consistent with the idea that direct RNA insertion into the axon would result in translation.

The following experiments were performed to determine whether axonal regeneration could be achieved by expressing proteins in axons that are linked to axonal growth. To express proteins in axons, RNA is transduced into the axoplasms using Sindbis, an alphavirus that has an RNA genome (Ehrengruber, Molecular Neurobiology. 26:183-201 (2002)). An internal ribosome entry site (IRES) was inserted into the RNA genome (Wu, Nature. 436:1020-1024 (2005)) allowing ribosomes to bind directly to the IRES and initiate translation of the RNA sequence downstream of the IRES.

Expression of Sindbis-IRES Viruses in axons

More specifically, Sindbis viral sequences were modified by replacing the subgenomic promoter with an IRES (Sindbis-IRES) (Wu, Nature. 436:1020-1024 (2005)). A sequence encoding (myr-GFP) was placed downstream of the IRES sequence. Myristoylated GFP does not diffuse away from the site where it is translated (Aakalu, Neuron. 30:489-502 (2001)). Rat embryonic (E) day 14 neurons were grown in compartmentalized culturing devices (Campenot, Dev Biol. 93:13-21 (1982); Taylor, Nature Methods. 2:599-605 (2005)). Neurons were plated in a cell body compartment connected to an axonal compartment via micrometer-thick grooves. After four days in vitro (DIV), axons had crossed into an axonal compartment. Sindbis-IRES virus expressing myr-GFP was applied to the axonal compartment. As shown in above, myr-GFP was only detected in axons, not in cell bodies or axons within the cell body compartment. This demonstrates that the virus had infected the axons and the myr-GFP was translated within the axons. The virus was not retrogradely trafficked to the cell body, since this would result in myr-GFP in the cell body compartment, and possibly the axonal compartment.

Expression of Soluble Adenylyl Cyclase in Axons

Treatments that result in increased cAMP levels in axons result in increased axonal growth rates and reduce the sensitivity to myelin. Sindbis-IRES viruses expressing soluble adenylyl cyclase with a myc epitope tage (FIG. 12) was prepared. Adenylyl cyclase is a cAMP-generating enzyme (Chen, Science. 289:625-628 (2000)) that promotes axonal growth Wu, Nat Neurosci. 9:1257-1264 (2006). As shown in FIG. 12, this protein was also readily detectable in E14 DIV4 rat sensory neurons cultured in microfluidic culturing devices when Sindbis-IRES-myc-sAC was applied to the axonal compartment. As before, no significant labeling was seen in the cell bodies or axons that lie in the cell body compartment.

Expression of a Dominant Negative RhoA in “Mature” Regenerating Axons

Inhibition of RhoA can lead to improved axonal growth and reduced sensitivity to the effects of myelin. To determine if axons that are regenerating can be infected by Sindbis-IRES viruses, and if these viruses can lead to protein expression, sensory neuron ganglia were harvested from postnatal (P) animals that were six days old. Harvesting these ganglia results in transection of their axons. The explants were dissociated and the neurons were cultured in microfluidic culturing devices, as above. After four DIV, axons crossed into the axonal compartment, and were infected with Sindbis-IRES-RhoA DN, bearing a mutation that renders RhoA inactive. As seen in FIG. 13, myc immunoreactivity was detected throughout the axons in the axonal compartment. No labeling was seen under control uninfected conditions. Additionally, negligible labeling was seen in cell bodies or in axons in the cell body compartment. These data indicate that regenerating axons from mature neurons can express a heterologous protein using the Sindbis-IRES system.

To further validate that cell bodies were not labeled when Sindbis-IRES viruses were applied to axons, Sindbis-IRES-myc-Cherry was used. This construct allowed for the detection of the transgene as a fluorescent protein. As can be seen in FIG. 14, application of virus to the axons did not lead to cell body labeling, while application of the virus to the cell body led to robust labeling. This demonstrates that the virus acted exclusively within axons in order to increase protein levels in axons.

In sum, these results demonstrate a viral approach to selectively modify gene expression in distal axons allowing for the introduction of proteins in injured distal axons and providing a new avenue to promote axonal growth in cases of traumatic nerve injury or axonopathies.

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All patents and publications referenced or mentioned herein are indicative of the levels of skill of those skilled in the art to which the invention pertains, and each such referenced patent or publication is hereby incorporated by reference to the same extent as if it had been incorporated by reference in its entirety individually or set forth herein in its entirety. Applicants reserve the right to physically incorporate into this specification any and all materials and information from any such cited patents or publications.

The specific methods and compositions described herein are representative of preferred embodiments and are exemplary and not intended as limitations on the scope of the invention. Other objects, aspects, and embodiments will occur to those skilled in the art upon consideration of this specification, and are encompassed within the spirit of the invention as defined by the scope of the claims. It will be readily apparent to one skilled in the art that varying substitutions and modifications may be made to the invention disclosed herein without departing from the scope and spirit of the invention. The invention illustratively described herein suitably may be practiced in the absence of any element or elements, or limitation or limitations, which is not specifically disclosed herein as essential. The methods and processes illustratively described herein suitably may be practiced in differing orders of steps, and that they are not necessarily restricted to the orders of steps indicated herein or in the claims. As used herein and in the appended claims, the singular forms “a,” “an,” and “the” include plural reference unless the context clearly dictates otherwise. Thus, for example, a reference to “an antibody” includes a plurality (for example, a solution of antibodies or a series of antibody preparations) of such antibodies, and so forth. Under no circumstances may the patent be interpreted to be limited to the specific examples or embodiments or methods specifically disclosed herein. Under no circumstances may the patent be interpreted to be limited by any statement made by any Examiner or any other official or employee of the Patent and Trademark Office unless such statement is specifically and without qualification or reservation expressly adopted in a responsive writing by Applicants.

The terms and expressions that have been employed are used as terms of description and not of limitation, and there is no intent in the use of such terms and expressions to exclude any equivalent of the features shown and described or portions thereof, but it is recognized that various modifications are possible within the scope of the invention as claimed. Thus, it will be understood that although the present invention has been specifically disclosed by preferred embodiments and optional features, modification and variation of the concepts herein disclosed may be resorted to by those skilled in the art, and that such modifications and variations are considered to be within the scope of this invention as defined by the appended claims.

The invention has been described broadly and generically herein. Each of the narrower species and subgeneric groupings falling within the generic disclosure also form part of the invention. This includes the generic description of the invention with a proviso or negative limitation removing any subject matter from the genus, regardless of whether or not the excised material is specifically recited herein.

Other embodiments are within the following claims. In addition, where features or aspects of the invention are described in terms of Markush groups, those skilled in the art will recognize that the invention is also thereby described in terms of any individual member or subgroup of members of the Markush group. 

1. An isolated nucleic acid comprising: (a) a mammalian translation initiation element; (b) a polypeptide coding sequence operably-linked to the mammalian translation initiation element, the coding sequence encoding a polypeptide that, when expressed in the axon of a mammalian neuron, modulates the growth or function of an axon; and (c) a viral packaging sequence.
 2. The nucleic acid of claim 1, wherein the viral packaging sequence is that of an alphavirus.
 3. the nucleic acid of claim 2, wherein the alphavirus is a Sindbis virus or a Semliki forest virus.
 4. The nucleic acid of claim 1, wherein the polypeptide-coding sequence encodes a polypeptide that promotes the growth of an injured axon, a kinase or a transcription factor.
 5. The nucleic acid of claim 4, wherein the kinase is a src kinase.
 6. The nucleic acid of claim 4, wherein the transcription factor is a cyclic AMP-response element-binding protein (CREB) or nervy.
 7. The nucleic acid of claim 1, wherein the polypeptide-coding sequence encodes a C3-ADP-ribosyltransferase, a dominant-negative RhoA mutant polypeptide, a cAMP-producing enzyme, glutamic acid decarboxylase, human proenkephalin, an inhibitor of a dominant-negative Vps24, an intestinal peptide (VIP), brain-derived neurotrophic factor (BDNF), neurotrophin-3 (NT-3), glial-derived neurotropic factor (GDNF), GAP 43 or CAP23.
 8. The nucleic acid of claim 7, wherein the dominant-negative RhoA mutant polypeptide is N19-RhoA polypeptide.
 9. The nucleic acid of claim 7, wherein the cAMP-producing enzyme is a soluble adenylyl cyclase.
 10. The nucleic acid of claim 1, further comprising one or more viral structural protein coding sequences.
 11. The nucleic acid of claim 10, wherein the structural protein is an alphavirus protein, capsid protein or a glycoprotein involved in viral assembly and packaging.
 12. The nucleic acid of claim 1, which is a recombinant RNA molecule.
 13. The nucleic acid of claim 12, further comprising a poly-adenylyl tail.
 14. The nucleic acid of claim 12, wherein the mammalian translation initiation element is a 5′CAP or an internal ribosome entry site (IRES).
 15. The nucleic acid of claim 14, wherein the IRES is a viral IRES sequence.
 16. The nucleic acid of claim 15, wherein the IRES is an encephalomyocarditis sequence, a Sindbis viral sequence or a Semliki forest viral sequence.
 17. The nucleic acid of claim 14, wherein the IRES is a prokaryotic or eukaryotic sequence.
 18. The nucleic acid of claim 14, wherein the IRES comprises the sequence of any one of SEQ ID NO: 29-35.
 19. The nucleic acid of claim 1, wherein the polypeptide comprises the sequence of any one of SEQ ID NO: 36 to
 47. 20. The nucleic acid of claim 1, wherein the polypeptide-coding sequence comprises the sequence of any one of SEQ ID NO: 49 to
 60. 21. The nucleic acid of claim 1, which is a single-stranded genome of a virus or an attenuated mutant thereof that is capable of infecting the axon of a mammalian neuron and transducing the recombinant RNA molecule into the axon.
 22. The nucleic acid of claim 21, wherein the virus is an alphavirus.
 23. The nucleic acid of claim 1, which is a recombinant DNA molecule that further comprises a mammalian promoter sequence located 5′ of the mammalian translation initiation element and wherein the mammalian translation initiation element is an IRES.
 24. A recombinant RNA virus capable of infecting the axon of a mammalian neuron, the virus comprising the isolated nucleic acid of claim
 1. 25. The recombinant RNA virus of claim 24, which is an alphavirus or an attenuated form thereof.
 26. The recombinant RNA virus of claim 24, which is a Sindbis virus, a Semliki forest virus or an attenuated form thereof.
 27. A composition comprising the recombinant RNA virus of claim 24 and a pharmaceutically acceptable carrier.
 28. A composition comprising the nucleic acid of claim 1 and a pharmaceutically acceptable carrier.
 29. A method for expressing a polypeptide in the axon of a mammalian neuron comprising contacting the axon with the composition of claim 27, under conditions effective for the transduction of the recombinant RNA molecule in the virus into the axon.
 30. The method of claim 29, wherein the polypeptide is one capable of modulating the growth or function of an axon.
 31. The method of claim 29, wherein the polypeptide is one capable of promoting the growth of an injured axon.
 32. The method of claim 29, wherein the polypeptide is one capable of reducing the activity of the axon of a neuron.
 33. The method of claim 29, wherein the polypeptide is a kinase or a transcription factor.
 34. The method of claim 33, wherein the kinase is a src kinase.
 35. The method of claim 33, wherein the transcription factor is a cyclic AMP-response element-binding protein (CREB) or nervy.
 36. The method of claim 29, wherein the polypeptide is C3-ADP-ribosyltransferase, a dominant-negative RhoA mutant polypeptide, a cAMP-producing enzyme, glutamic acid decarboxylase, human proenkephalin, an inhibitor of a dominant-negative Vps24, an intestinal peptide (VIP), brain-derived neurotrophic factor (BDNF), neurotrophin-3 (NT-3), glial-derived neurotropic factor (GDNF), GAP 43, CAP23, a myc-tagged soluable adenylyl cyclase, a green fluorescent protein (GFP), a myristoylated GFP, a destabilized enhanced GFP (dEGFP), a myristoylated dEGFP, Cherry, or a myc-tagged Cherry.
 37. The method of claim 36, wherein the dominant-negative RhoA mutant polypeptide is N19-RhoA polypeptide.
 38. The method of claim 36, wherein the cAMP-producing enzyme is a soluble adenylyl cyclase.
 39. The method of claim 29, further comprising contacting the axon with a brain-derived neurotrophic factor (BDNF), neurotrophin-3 (NT-3), glial-derived neurotropic factor (GDNF), nerve growth factor or a combination thereof.
 40. The method of claim 29, wherein the axon is that of a sensory neuron, an upper motor neuron or a dorsal root ganglion.
 41. The method of claim 40, wherein the sensory neuron is a peripheral sensory neuron.
 42. The method of claim 29, wherein the virus is applied to the axon at a site of injury.
 43. A method of treating a condition in a mammal associated with aberrant axon function comprising administering to the mammal the composition of claim 27, wherein the composition is administered locally to one or more selected axons.
 44. The method of claim 43, wherein the condition is axon injury associated with spinal cord injury, laceration, a stroke, multiple sclerosis, axonal degeneration associated with axonal injury, diabetic peripheral neuropathy, neuropathic pain and/or inflammatory pain.
 45. An isolated mammalian neuron, the axon of which comprises the nucleic acid of claim
 1. 46. The isolated mammalian neuron of claim 45, which expresses a polypeptide encoded by the nucleic acid.
 47. The isolated mammalian neuron of claim 46, wherein the polypeptide is one that modulates the growth or function of the axon of a mammalian neuron when it is expressed in the axon.
 48. A method for introducing an isolated nucleic acid into the axon of a neuron comprising contacting an alphavirus comprising the isolated nucleic acid with the axon.
 49. The method of claim 48, wherein the isolated nucleic acid comprises: (a) a mammalian translation initiation element; (b) a polypeptide coding sequence operably-linked to the mammalian translation initiation element, the coding sequence encoding a polypeptide that, when expressed in the axon of a mammalian neuron, modulates the growth or function of an axon; and (c) a viral packaging sequence.
 50. The method of claim 48, wherein the nucleic acid comprises the sequence of any one of SEQ ID NO: 29-35, 36-47, 49-60. 